Tuning
From: douginbhm
Subject: Re: Electronic tuner
I
have a tuner that sounds just like what you asked about. I haven't tried it out
because I sprang for an electronic tuner instead. You can download it at: http://alpha.bzlogi.hu/~laci/minituner.html
target=new>http://alpha.bzlogi.hu/~laci/minituner.html
It's freeware.
With regard
to the chrome tubing that you mentioned. I've thought that I would try chrome
plated brass tubing which I think is available as shower curtain rod. Doug
From:
Brewmeister999
Subject: Bass Chimes
I
was lucky enough at my job to get the leftovers of a pneumatic tube system
installation. These steel pipes are 6 inch diameter tubes, the longest piece is
about 6 feet long. I have been waiting for a method of tuning them to come
along, and I think I found it here. One of you posted a link to an automatic calculator
that hopefully will cut down on the amount of cutting/tuning for me. http://www.oocities.org/cllsj/length.html
Hacksawing 3/4" conduit is one thing, but these babies ain't fun!
From: joe2you2
I've been making
chimes for several years and have developed a few spread sheets which might be
of use. In determining the tuning of a chime I've come to the conclusion that
it's not necessary to match an exact frequency on the first pipe as long as the
rest of the pipes are tuned to the first. That being said it is now easier to
determine how much material you need to make a chime or how much chime you can
make with a given amount of material. Someone posted a question regarding what
a commercial windchime is made from. Most of the "good" chimes I've
seen are made from Aluminum grade 6061 with a T6 temper roughly 1"
diameter with .030 wall thickness. Kind of expensive, but worth every penny. I
made one with 8 2" pipes and I can tell you there's nothing like it in the
world. Joe
From: rgupton01
Subject: Re: Conduit Chimes
The
tuning is here. http://www.monsterbit.com/mots/sizes.html
I apologize
for missing that before posting my earlier message.
From: "Jim
<zeebugman@yahoo.com>"
Subject: Hear what you want to make before you make it!
I ran across a gem I had downloaded a couple
years ago in my web-quest for a tuning application. It's shareware so you can
try it for free. If you can think of the sound you want to create with your
chimes, you can hear it with this program. And it will tell you what the notes
are. Instruments and sounds...choose the mood...select the # of chimes...
pendulum spacing....even adjust the wind from calm to stormy! It's really an
awesome program/tool. I used to set it to my mood (or where I wanted to be) and
let it run in the background. Care to hear what your chimes would sound like on
bagpipes, steel drums or a bird chirping it...give it a shot. Jim
http://www.syntrillium.com/windchimes
Now owned by Adobe and no longer free. Teeley2
From: cllsj
Subject: Re: tuning of tubes
"oldwisebison2002 wrote:
> what
does the cutting of 30 degrees or 45 degrees do for tuning and > sound
quality of 1.5 and 2.0 in. tubes. Also, where can I buy 1/4 by 8 in and 10 in
dia. chrome upper rings, I've seen them on chimes out of Texas.(alum. conduit)
A friend
wrote me with the following
I cut the
ends of my tubes on a slight diagonal to give a 2-3 Hz difference depending on
what dimension gets hit. This gives rise to a 2-3 Hz beat frequency, you know
"wow-wow-wow",:)
http://www.onlinemetals.com/
Above is a
link to another source for all sorts of shapes, sizes, and materials.
From:
"bmh1944" <bmh1944@yahoo.com>
Subject: Re: Chromatic windchimes - our experiment
Jay;
I think
your experiment was a great success. After listening to your audio files, I'm
expecting you to practice up a bit and post a little of Beethoven's Ninth
Symphony for me (OK, so I'd enjoy something from Chuck Berry more - LOL).
Somehow (after raising two children myself) I shudder at letting the kids use a
brass mallet on copper chimes; I suppose I'd let them practice with the rubber
mallet first, then graduate up to, perhaps, small plastic hammers (for
dent/destruction
prevention
measures).
I applaud
both your success and the fact you got the kids involved with the project;
perhaps if we adults spent more time getting involved with our kids in many fun
projects, the kids wouldn't be spending their time finding counterproductive
entertainment. While some of us (myself included) tend to become obsessive with
tuning, materials, and exact sciences, my sane side still manages to hold 51%
of the mental stock - which keeps everything in the "fun, interesting, and
enjoyable" category. For that one reason alone, Jim Haworth probably
states things in the perspective I've always pursued translation: "hey,
this is supposed to be fun - don't make yourself crazy with technicalities to
the point where the fun goes away").
I will give
you a little insight on using "tuners" (of any sort) for chimes
because I daily struggle between being both an electronics engineer for 38
years and a musician for about 53 years. When it comes to music, you must trust
your ear's perception over that of all the mechanical or software "audio
analyzers". All of the tuners and/or audio analyzing devices see and
display sound as it's really present (and being produced) on a strictly linear
basis of both amplitude and frequency; unfortunately, the human ear is probably
the most non-linear, narrowband, sound reproducing device on the planet. Like
all other percussion instruments, chimes DO NOT produce a range of fundamental
and pure harmonic frequencies (octave equals) like stringed, wind tube, reed,
and synthesized instruments produce; instead, there are numerous, non-harmonic
overtones present which (depending on their individual frequencies and
amplitudes) can be very predominant on an "analyzer or tuner", yet
make little or no difference to the human ear. Likewise, something a "tuner"
may show as a predominant (amplitude) frequency may not be what your ear
actually perceives as a result of the brain's "fuzzy logic" giving a
perception of many different overtones associated with a particular fundamental
frequency.
If you wish
to get obsessive with tuning, Chuck and Jack both have extremely good
engineering/scientific based methods of finding the "ideal" length
(in the "links" section here) for a particular length/OD ratio which
produce the best "musical note" interpretation (to the human ear) for
a tuned tube that comes closest to giving the proper "ear candy" to
perceive a particular note in the musical spectrum. But, whatever path you wish
to explore, don't forget Jim Haworth's advice about keeping it all in the
"fun and enjoyable" category; if you wish to go beyond that criteria,
Jack and I can give you good places to buy plenty of cheap beer - LOL. Brent
(Fred Flintstone)
From: cllsj
Subject: Re: tuning the air column like a flute
suppanz wrote:
> I see
some people trying to match the resonance of the tube vibration with the
natural frequency of its air column to get longer sustain and better sound. Has
anyone tried tuning the air column by drilling holes like a flute?
> Brad
It doesn't
work. For a flute or an organ one is forcing air through the tube. When I tune
the chime to the column of air I'm trying to induce a standing wave in the air
column. Only by making the transverse vibration mode of the tube nearly the
same as vibration mode of the standing wave does this work. Small holes (at
least) just don't matter. If they did drilling a hole to suspend the tube would
ruin the whole thing. Larger holes probably would have an affect not only on
the column of air but also on the transverse vibration.
Yes, you
can close one end of the tube and force a node. It does change the math some
but with the rather simple equations and a spreadsheet this shouldn't be too
hard to figure out. I found that when I tune a tube for the fourth natural
frequency it doesn't seem to make a difference, that I can hear, between
hanging them at the first node or closing the end and hanging them from the
end. I guess I've not gone back and tried this for the first natural frequency
tubes. chuck
From: "slakk2001"
<slakk2001@yahoo.com>
Subject: Free Tuner for PC
Hi everyone. Over the last few weeks I'm been
searching on the net for tuners for the PC. I found a FREE one that works. It
called wtune. Here's the link: http://www.cipoo.net/wtune_e.html
On a
personal note.... I ended up buying a tuner called the Chromatia Tuner v3.0 for
the PC. It's one of the best I tested and reasonable ($19.95). Here's the link:
http://www.fmjsoft.com/ctframe.html
Rick
From: <david@enete.org>
Subject: Re: Free Tuner for PC
I'll
"chime in" on this one. For about the same price, you could purchase
a Korg CA-30 chromatic tuner. It is a fairly fast tuner that works very well.
It will allow you to change your pitch calibration if you so desire and it has
a tone generator.
I have used
the Peterson strobe tuners, Yamaha TD-1, Sabine Metrotune, and the Korg CA-30.
The Peterson is great. The Sabine is dismal. The Yamaha and Korg are accurate.
The Korg however, is highly affordable and very fast. I strongly
recommend
it when considering a tuner. It can be found on the Internet for $19.99.- David
From:
"bmh1944" <bmh1944@yahoo.com>
Subject: Re: Frequency of Chime?
Welcome to
the world of frustrated obsessive/compulsives - haha. Being a musician for
about 50 years now, I truly feel empathy for those trying to "tune" a
chime or bell to any exact musical note for two simple, nasty little variables
(overtones and human ear perception) that few mathematical formulas can ever
calculate with any degree of exact accuracy. First of all, you're best efforts
will probably be in staying with shorter tubes that are "tuned" to a
fundamental frequency at or above the fourth octave because there's fewer
overtones (in practical human hearing range) to contend with
and mess
with the end result.
OVERTONES: By different characterics
and principles, strings, reeds, horns, and organ tubes produce only the
fundamental sound frequency that one perceives at a single musical note. Higher
frequencies which result (from the instrument's body or containment tube) are
exact harmonics (multiples) of the fundamental frequency. The
"timbre" difference is noted from whatever degree and ability (if any)
the instrument's body can sustain or amplify the produced harmonic frequencies.
In either case, the fundamental and any harmonics are all exact multiples
(octave range) and are all "in tune" with each
other.
When a
solid rod or tube is suspended from a node (point of least vibration), many
different things happen because (for all practical purposes) the object is
vibrating in a physically unrestrained environment that allows many different
wave propagation pulses to simultaneously travel in a very complex pattern of
many opposing directions and different vector variations of each direction.
Striking a solid rod or tube allows the
fundamental "big dog" frequency (the one running the linear length of
the object and exciting the most surrounding air movement) to sustain in the
resonant linear length environment; but, at the same time, a much higher
frequency finds resonance at the cross-sectional wavelength of the rod's
diameter; then, to a certain degree, a spiraling wave of lower-than-fundamental
sees resonance at some spiraling length that's longer than the true linear
length of the object. These different frequencies "add" to the linear
fundamental) through both logarithmic and complex trigonometric vector addition
of different phase angles) which, by the same process, "add" to what
should be the first harmonic to produce a higher-frequency "first
overtone". Now that the first overtone is present, it must be also
factored in to everything (that already exists) to "add" an even
greater amount to what should be the second harmonic to produce the
"second overtone". Therefore, because each succeeding "virtual
harmonic" sees a greater "addition" of everything already
present, each "overtone" is a higher decimal multiplication factor of
the fundamental than the previous overtone.
This all
works great on paper, but since the varying characteristics of wave propagation
speed differ with each particular type of metal and/or alloy of the same metal,
there are also inherent slight differences in the cross-sectional and spiraling
wave frequencies (with respect to the linear fundamental) through the different
mediums. That's part of why the noted differences in particular overtone
results (with different metals) causes little "math" anomalies to
confound us. In a hollow tube, there is a tiny cross-sectional difference
"added" by only the wall thickness, another influence comes from
cross-sectional air-column influence, the linear air-column movement plays
another small role, and the spiraling outer
surface
waves become more pronounced than those of the solid rod. All of this combines
to further cause slight variations in the "math" between different
metals of different diameters and wall thickness.
Of course,
the longer the tube and lower the resulting fundamental frequency, the more overtones
(in audible range) will be present to further mess with your
"perception".
PERCEIVED
SOUND:
Your eyes literally "photograph" every frame of a "movie"
running at 15-20 frames/pictures per second, convert each "digital
snapshot" to electronic impulses, and feeds the whole mess to the brain
for "perception". Since the brain doesn't like "digital"
anything or a conglomeration of mixed signals, it uses "fuzzy logic"
to convert all information into a smooth "analog perception" that
looks just like you'd see in "real time" from a truly analog source.
The ears do the same magic with the jumble of fundamental frequency and many
overtones (which are NOT true harmonics); so, regardless of what all the
machinery tells you is present, your brain will take the whole combined mess
and give you
some
"fuzzy logic" perception of the total - which many times does NOT
agree with the particular note or "pitch" you think you should hear.
The more overtones present, the more "fuzzy logic" messes with the
true representation of what is actually present.
TUNING
FOR A MUSICAL NOTE: You'll be best served by cutting a shorter tube or rod for a
higher, mid-range fundamental
frequency,
or strike a longer tube in a place that gives only a few predominant overtones
- simply because there won't be such a mudddle of predominant frequencies for
the brain to "fuzzy logic" into some perceived "note".
But,in the best of cases, there will NOT be a perfect musical note because none
of the overtones or fundamental will be a pure harmonic or sub-harmonic
(octave) with respect to each other; something will be a little "right
on", something else will be a little "flat", something else will
be a little "sharp", and something will be off in left field from the
"pure note". The more un-
harmonic frequencies
that are present, the more difficult it will be to "perceive" any
exact note. For example: Cutting a tube to a fundamental of C3 (130 Hz) - the
1st overtone (360 Hz) is in the "crack" between F4 & F#4 - the
2nd overtone (706 Hz) is very close to F5 - the third overtone (1168 Hz) is
right at D6 - and the 4th overtone (1745 Hz) is pretty much A6. So, let your
brain do a "fuzzy logic" addition of C3, F/F#4, F5, D6, and A6 - then
have fun lining up that single "perceived note" to a single key on
the ole' piano!!
There's a
tremendous amount of really good information, websites, and articles available
through the links listed here in the group; perhaps the most appealing and
simplest thoughts on tuning (at least to Fred Flintstone here) is an article by
Jim Haworth where one simply cuts a tube to some length that trips your
trigger; then, using a not too difficult math formula, one can use that tube as
a "starting point" and figure the length for each chromatic musical
step from that point to get in the "ballpark" for more fine tuning.
Lee Hite's Excel chart and spreadsheet calculator is another good
"ballpark" guide for getting things close to some desired length (but
there's still the occasional "goctha" that suddenly doesn't
sound like
it should at all).
Just
remember that it's very difficult to actually get a perfect "note"
from the perceived sound of many different notes all running at once. You'll do
pretty well through a few tubes in getting them to "agree" in a
musical scale; then, suddenly (for no reason) the perceived "general
note" on the next logically cut tube will turn on you and sound totally
different - especially if your set is traversing two or more octaves. So, just
be prepared for some heavy drinking and running through your entire repertoire
of foul words (a number of times) before getting something you're happy with;
of
course,
then the wind won't play your tune anyway. Tuning for anyone who is a
non-musician is a bit easier (just ask my wife); but for someone with a very
musically perceptive ear, chimes will make you crazy in trying to tune for
anything "exact". I've got a few long-tube sets that are
"tuned" in some fashion of note progression (with respect to each
other) and a few sets that are simply random length; since the wind seldom
strikes anything in any order but random, I really can't say that I prefer
either the tuned or random sets – both sound very nice when the wind just does
it's thing. Brent
From:
"bmh1944" <bmh1944@yahoo.com>
Subject: Re: Tuning and correction factors
Marty;
All
length/OD/frequency calculators are built around Euler's mathematical/physical
theorems concerning such. While those
principles
are true in the world of spectrum analyzers and physical reality, the poor
response curve of the human ear combines with the brain's "fuzzy
logic" process to completely toss a monkey-wrench into what we "perceive"
to hear compared to what is actually present. Translation: what is actually
there isn't always what we "hear" and perceive as being there.
Chuck (and
Jack) have a great "ideal length" calculator that keeps an optimum
OD/length ratio (plus other closely guarded factors) within a realm that helps
preclude all those nasty things which start to happen (especially at longer
tube lengths) when the additional, non- musically harmonic, lower frequencies
trigger the brain's "fuzzy logic" process into completely defying
what the reality of both math and physics indicate is present. This is the
reason that most calculators have some sort of "correction/fudge
factor" that, as you've seen, also vary when using the same type of
material at
different
lengths. The math and physics aren't wrong and don't need any
"correction"; it's simply a "shot-in-the-dark method" of
trying to compensate for what the ear and brain "perceive" from that
which is really there in reality.
When you're
probing those longer lengths (outside Chuck's "ideal length"
criteria), the slightest length difference in a particular tube will change
what is actually produced by a mathematically correct increment. BUT (for
reasons I can't explain), the amplitude changes of the fundamental frequency
and related overtones which result from this change in a very long tube's
length (beyond Chuck's defined "ideal length") can suddenly cause the
brain to perceive a very radical change (in dollars - not "cents") in
the "musical note" one perceives as a result of the new
"mixture" of frequency/amplitude
ratios.
Tuning very
long tubes is not impossible, but keep plenty of cheap whiskey on hand and a
soft spot on the wall to beat your head against when taking on such a task.
Fred Flintstone (here) has a nice assortment of many tubes that were cut to
some desired note (with the "correction factors" applied) that
actually produce an entirely different "perceived" note. Hey, I'm not
stupid - I just labeled each one (using a magic marker) to the "note/pitch"
it produced; and, someday I'll make a huge, diverse set of different diameters
and metals to play Beethoven's 5th - LOL.
Anyway,
taking this curse of the brain's "fuzzy logic" process into
consideration, you'll notice that making a wide-ranging set of chimes (whether
orchestra chimes or using Chuck's "ideal length" criteria) is only
facilitated by using different lengths of different OD tubing. All the
"correction factors" to Euler's theorems cannot cover all the bases
for all tubing when it comes to what the brain's "fuzzy logic" allows
us to hear and perceive. Brent
From:
"bmh1944" <bmh1944@yahoo.com>
Subject: Re: Alternative tunings revisited
Marty;
Your
alternative tuning would be interesting to hear about what results you get.
Much of the recent bantering of late has been how to get a reasonably
predictable result from ANY tuning - LOL. I've tried a number of experiments in
the past in tuning for a second, third, or fourth natural frequency (with the
actual fundamental being whatever necessary for the desired overtone); but,
that's where all the things that circle to bite the backsides seem to begin popping
up with very
unpredictable
"perceived" results.
I
still enjoy cutting long tubes and playing with the length a little to get the
best sustained "ring", but I leave any "tuning" of a set
like that to whatever happenstance in diversity that varied lengths end up
producing. Longer tubes (outside "ideal" length) DO produce the
projected fundamental and related overtones; but their relative amplitudes
(compared to each other) can radically change with only minor length variations
(i.e. a nicely ringing long tube minus 1/4
inch in length
suddenly becomes either a "clunk" or suddenly produces a totally
"different than expected" perceived note for no reason).
All the
Euler-based spreadsheets seem to indicate that one can "tune" any
single OD of tubing to any desired note or octave by variations in length.
While this is both mathematically and physically correct, it (again) doesn't
give relative and changing amplitude levels of the individual frequency
components (or their occasional interaction with each other) as length varies;
and neither do those same calculators consider the terribly poor response curve
of the human ear which
combines
with the brain's fuzzy logic process to generate many unexpected surprises.
My long-tube
experiments have shown that one can, indeed, predict the natural frequencies
present in a tube of any particular length/OD ratio; but, since any particular
length/OD ratio and metal property may produce entirely different respective
amplitudes of those inherent frequency components as length changes, it becomes
very difficult to predict just which one of those fundamental or overtone
frequencies will be predominant at any given length.
Chuck's
"ideal length" calculator hits the nail right on the head when you
use it to explore tuning at the First Natural Frequency. The bottom line there
is to plug-in various ODs (of any particular metal composition) until you get
into the "ideal range" at the first natural frequency. Then, the
predominant frequency will almost always be the fundamental or first natural
frequency with overtones not playing a major role in either note/octave
perception or triggering the brain's fuzzy logic process into, perhaps,
interpreting something different. If one looks at Chuck's figures in that
arena, they are almost exactly in line with OD/length ratios of orchestra
chimes, premier windchime sets, and even the slightly "mechanically
tunable" Deagan chimes of 100 years ago. One will usually see very high
notes in the C9 range using 1/2"OD tubing or less; and, as the octaves
proceed on down, one will see at least 6"OD for anything in the C1 range.
So, when
I'm going for precise tuning of any type, scale, or method, I start out with
the right OD for the right note/octave "ideal range" using Chuck's
calculator at the first natural frequency. Brent
From: cllsj
Subject: Re: More Tube Stuff
Well, here I am wrong again. Copper tubing
used for water pipe is 99.9% pure copper. I found this in the "Copper Tube
Handbook" by the Copper Development Association and available online (20MB
pdf file).
However, I
was correct about the speed of sound in copper being lower in copper than
aluminum. C12200 copper used in water pipe (see the handbook) has a modulus of
17e6 psi with a density of .323 lb/cubic inch (the material properties came
from efunda but other sources can be found). This gives a speed of sound for
copper
142607
in/sec
for
aluminum using a modulus of 10e6 psi and .1 lb/cubic inch
196570
in/sec
for steel
using a modulus of 30e6 psi and .283 lb/cubic inch
202389
in/sec
So the
speed of sound in copper is about 27% lower than in aluminum.
Two errors
(welding copper and purity of copper in water pipe) and one right (speed of
sound in copper versus aluminum). Not a very good ratio. I will have to try to
do better. Chuck
From: "Mark
Harris" <marksjob@cox.net>
Subject: Mark Harris -- steel & copper
I got a big laugh out of the idea of welding
copper. I can't talk from experience, but, the temperatures of each metal will
be the same
for silver soldering. You can't, to my knowledge tin solder stainless. Silver
solder requires a lot more heat. The copper will be cherry red, but no, you are
not getting close to melting the copper.
Stainless
and copper are about opposites in heat handling. Copper, like aluminum wants to
dissipate heat very quickly so it requires more heat.
Stainless doesn't know what to do with it,
and can be more easily overheated. The one consideration you may have silver
soldering between the two is the flux. Check with the welding shop and see if
the flux is compatible with both metals. Then silver solder several pieces of
scrap. It will probably be easy to from an oxide on the stainless that will
inhibit the solder from heating too much or too slowly. A weird dichotomy! I
would predict this will be the difficult part. Mark
From:
"bmh1944" <bmh1944@yahoo.com>
Subject: Tube Wall Thickness Questions - Duh??
Chuck has raised a good question about the
concept of how (if any degree at all) a hollow tube's particular wall thickness
would/could play any role at all in affecting the speed of kinetic energy wave
propagation (ok, call it the "speed of sound" if you wish) between
two tubes of identical OD, same length, and exact same metal alloy, but with
different wall thickness. Again, I offer no math for the perceived difference
between thin and thick walls of the same material; my only source of
information comes from what I've deciphered from the metallurgist’s thoughts,
and from a limited amount of my own experimentation.
When
comparing the exact same material properties, Lee Hite's Excel spreadsheet (for
length calculation) seems to support this theory. When one only changes the
wall thickness (OD vs. ID) as plug-in's to the formula, the thicker wall
produces a shorter tube for the same resonant fundamental with all other
constants, variables, and correction factors remaining the same (which seems to
indicate an apparent "slowing" of wave propagation speed as the
tube's walls become thicker).
Additionally,
both Lee's (and others') comparative charts for tubes of the same metal with
different diameters show intriguing results.
Take
1" OD aluminum vs. 3/4" aluminum tubes for example; both tubes are of
the same metal composition and have the exact same FFT, modulus of elasticity,
assumed identical hardness factor, and the same .0625" wall thickness -
yet, the smaller diameter tube shows roughly an "apparent 15% slowing"
of wave propagation speed because the "math" results in a 15% shorter
tube to produce the same fundamental frequency.
Yes, I
understand there is probably some very complicated set of formulas to justify
why an apparent 15% decrease of wave propagation speed (in identical metal)
results from a 25% decrease in a hollow aluminum tube's outer diameter and
(with wall thickness remaining the same) a corresponding 25% decrease in inside
diameter. Yes, as I've preached, the smaller air-column volume in a given
length of 3/4" tubing will play a lesser measurable role than the larger
volume of air will provide within a larger diameter tube. But, here's where
Fred Flintstone (of limited intelligence and massive ignorance)
starts
feeling a rub of discord and major confusion.
I've found
Lee Hite's charts and Excel spreadsheet to be very good at providing a nice
"ballpark" starting point for length vs. desired frequency (after the
"fudge factor" is determined) for different diameter tubing of
different compositions; because of this, I use his pre-figured results for both
1" OD aluminum and 3/4" OD aluminum (with exact same .0625" wall
thickness) as a base for my confusion and questions that I'm unable to answer.
Not only does Lee's Excel calculator show a "slowing" of wave
propagation speed as wall thickness increases (for the same OD tube of the same
metal), but I start to wonder about the differences his pre-figured charts seem
to indicate. Looking at length comparisons for a fundamental resonance at C2
(keeping wall thickness at a constant of .0625"), a corresponding 25%
decrease (in both OD and ID) creates an apparent 15% decrease in wave
propagation speed (speed of sound - grrrrrrr) which results in a 15% decrease
in tube length to achieve the same resonant length for C2. BUT THIS IS NOT A
TRUE "APPLES TO APPLES" COMPARISON!! To get things on a level playing
field of a TRUE RATIO COMPARISON, a 25% decrease in OD would have to be offset
by a corresponding 25% decrease in tube-wall thickness to achieve the same
ratio of "OD to ID" in the 3/4" tube as that of the 1"
tube. I would think that a true comparison would be to also reduce the 1"
tube's .0625" wall thickness by 25% to a wall thickness of .0469" in
the 3/4" tube - then, make another "just for giggles" comparison
to see if the wave speed/length disparity remained unchanged (am I correct in
this assumption, or just wallowing in ignorance again??).
Since the
major fundamental frequency's resonant wavelength measurement (for a hollow
tube) is primarily based upon the end-to- end, straight line, LINEAR distance
covered by one wavelength of the high-amplitude "peristaltic" wave
that travels the linear length of the tube, my ignorance is probably the main
factor that causes me to ponder a number of questions. Is there very close
mathematical justification that a 25% increase/decrease in cross- sectional,
"hollow tube" diameter (of exactly the same metal and FFT properties)
should cause a 15% change in the "apparent" linear wave speed/length?
Other than a different degree of internal air-column influence, how does a
change of cross-sectional distance in a hollow tube influence a linear wave
propagation (speed of sound) to such a great degree? Is this apparent change in
linear wave propagation speed (and corresponding tube length) caused by a
cross-sectional difference in nothing but air - or a greater linear impedance
to wave propagation speed from a thicker wall providing a wider avenue for
non-linear energy transfer vectors to move "off course" before being
channeled back (by physical limits of the wall) before continuing on in the
right direction? Would an equal physical ratio of a 3/4" OD aluminum tube
(with a .0469" wall thickness) produce the same apparent wave speed/length
disparity when compared with a 1" OD tube with a .0625" wall
thickness?
Perhaps I'm totally off base in concept, and
some of my "Fred Flintstone" experiments with wall thickness were
influenced by some difference in alloy composition or some other unknown factor
that made a noted difference between the thin wall and thick wall tubing.
But, again,
I've also had bad experience from noting a different resonant fundamental being
produced by the same tubing, from the same manufacturer, of the same
"rating", same wall thickness, but different manufactured lots; so,
even in supposedly "identical" material it seems that unknown
variables abound. Brent
From:
"bmh1944" <bmh1944@yahoo.com>
Subject: Re: Will drilling change the pitch?
The pitch or perceived tone of your tubes is
primarily determined by their particular length and not affected to any degree
by drilling holes at the measured "node" point. Even though this
"node" point is the one of least vibration for the fundamental
frequency, there is still a considerable amount of vibration present from any
and all overtones (which do not have a "node" at that point). So, any
particular hanging method (good or bad) at the "node" will give some
degree of impedance to the tube's ability to sustain vibration (as compared to
what it could sustain if magically levitated with no suspension at all).
Hypothesizing
again, smaller diameter mounting holes would create less overall interruption
in the tube's normal wall consistency, and (perhaps) have a lesser dampening
affect than larger mounting holes. In either case, I'd recommend using the
smallest diameter holes and either the smallest diameter axle or mounting line
that was practically possible for the least amount of dampening effect on the
tube's ability to sustain it's produced sound. Brent
From:
"Rick" <slakk2001@yahoo.com>
Subject: Re: Doug is finally done - new photo
You've made a great looking set of chimes!
Thanks for the free tuner link also. It's a nice one, and as accurate as the
one I bought for my PC. I was in the same boat as you.......grind away, then
run to my computer to see if I was getting close, then head back to the
grinder, etc. Can't say it wasn't good exercise! Thanks to David (nasagliders)
he recommended a good hand held tuner, which I eventually bought. It's a Korg
CA-30 chromatic tuner. I found it on the net for only 13 bucks + $2.95
shipping. Here's the link if you, or anyone else is interested.
http://www.crossroads-music.org/catalog/tuners_66042_products.htm
Now I have
it next to my grinder, which really saves time. Rick
From:
"Rick" <slakk2001@yahoo.com>
Subject: Re: New member - 4 x 26 inch pipes
Hi Benjamin,
Here's a
list of tuners that should help you. As Doug mentioned, you'll have to haul the
tubes to your computer.
The Korg
CA30 is a nice small hand held tuner, but doesn't give a frequency readout.
Rick
-------------------------------
Trial/Shareware:
Chromatia
Tuner 3.0:
http://www.fmjsoft.com
-------------------------------
Free Tuners:
wtune:
http://www.cipoo.net/wtune_e.html
MiniTune:
http://vacworld.bzlogi.hu/minituner/index.html
--------------------------------
Hand held:
Korg CA30
Chromatic Instrument Tuner
Bought this
tuner for $13 at Crossroads Music
http://www.crossroads-music.org/catalog/tuners_66042_products.htm
From: <pjporham@rockwellcollins.com>
Subject: Re: High school physics project
Have you talked
to the music department?
They may be
able to use a set of orchestra chimes.
If they
could use a set of chimes in a chromatic scale you could anodize gold and black
(like a the keys of a piano)
If you have
a machine shop and electronics department, they could build them and fine tune
them.
This is a
project that I am working on now:
http://www1.iwvisp.com/cllsj/windchimes/length.htm
Aluminum
6061 T6
NOTE Freq
OD ID
4G 392 1.25
1.1875
4A 440 1.25
1.1875
4Bb 466
1.25 1.1875
5C 523 1.25
1.1875
5D 587 1.0
0.9375
5E 659 1.0
0.9375
5G 698 1.0
0.9375
5F 784 0.75
0.6875
5A 880 0.75
0.6875
5Bb 932
0.75 0.6875
I have been
experimenting with 2 tubes tuned to 4A (440Hz) one tube is 1 inch OD, 69
inches, 4th natural frequency, and other is 1.25 OD, 60 inches tuned the 3rd
natural frequency. I prefer the sound from the 1.25 inch OD tube.
Tubes are
from www.windchimesbytheinch.com
Philip
From: "Brent"
<bmh1944@yahoo.com>
Subject: Re: Hole location...
Hi
C;
Bill is
correct; and if you wish to get really technical the transverse mode's
"node" point is described as 22.42% of the tube's total length or
(.2242 X length). The tube's material composition, OD, wall thickness, and
length will all enter into what particular fundamental (or first natural
frequency) will be produced, but the point of least vibration (node) will
always lie at the above described mathematical point.
You figured
right in the idea that tuning a chime AFTER you drill the mounting holes is
very counter-productive if you have to do any shortening of the tube by any
appreciable degree to "tune" it. As the tube gets shorter, the
position of the node mounting hole will change as a result; so, even though you
may get one tuned, the hole will not be at the actual node point and cause a
considerable amount of dampening to the tone.
A major
gotcha in building and tuning windchimes is trying to use the ASE (American)
standard of measurement because plugging fractions into a calculator don't work
until you go to all the hassle of converting them to decimal equivalents first.
If you're going to do much chime cutting and tuning, I strongly advise running
off to Home Depot, Loews, or any other hardware store and getting an
inexpensive tape measure that's both ASE and Metric. It's so much easier to use
many of the charts and measure everything in millimeters because you can do the
math much easier without all the conversion hassle.
I've had a
lot of success in tuning a tube BEFORE drilling any holes using an old trick
that I'm embarrassed about not remembering who authored the idea - but it works
very well. Basically, you horizontally suspend the tube at BOTH node points
(.2242 of the total tube length from EACH end). You can either suspend it using
a couple of long loops of thin monofilament line, or a few thin rubber bands
which have been square-knotted together by pulling one through the other. The
tube should be suspended from a horizontally mounted, fixed rod or bar that's
fairly rigid to prevent any slight vibrations
from being
transferred from the chime tube being tuned. One can use a rigid piece of cast
iron plumbing pipe, rigid EMT conduit, or my personal favorite of a 6' T-post
(used for livestock fencing). I like the T-post because it's triangular shape
makes it easy to use a couple of C-clamps to clamp it securely across the top
of a stepladder where a round object would be more difficult to keep steady and
secure.
Here's
where the metric tape measure comes in very handy for constantly re-figuring
the node points as you cut the tube a little shorter during the tuning process.
In either case, you simply measure the "node" point on the tube
you're starting with, then suspend it from that measured distance (from each
end) by using the monofilament loops or rubber bands to hang it from the
support rod you've clamped to the ladder. The mono loops should be long enough
so the tube hangs at least 6" below the support bar so there's little or
no dampening of the slight vibrations which are still present at the nodes.
Strike the tube at the point you intend to have it hit (end or middle) and
measure the produced frequency with any of many devices or methods listed here
on the site. After you've used the math to figure approximately how much you
need to remove to make your first tuning check, re-figure the node point and
adjust your suspension loops to the new points and strike the tube again for
the next frequency measurement. Using this method, you can keep changing the
node suspension points as the tube length is changed; once you've gotten it
tuned to your satisfaction, THEN drill the holes. Brent
Brent" <bmh1944@yahoo.com> ?
You
are right in your assumption "C"; there are two "nodes"
(points of minimum vibration movement) on a resonant tube under standing wave
conditions (.2242 X total length from each end), and three "antinodes"
(crests, peaks, or points of maximum vibration induced movement) which lie one
at each end and one in the middle of the tube's length. Striking a tube at
either antinode will produce the best excitation of the resonant fundamental;
and most good windchime sets have the individual tubes suspended so the striker
either hits each one in the middle - or sometimes, at the lower end on sets
with longer tubes.
I've found
that striking a tube in the middle seems to excite the higher natural
frequencies a little more than the fundamental and lower overtones, and
striking a tube on the lower end gives a fuller, louder sound because it seems
to excite all natural frequencies to the greatest degree. An end strike can
create a problem in longer tubes where one has tried cutting it to favor the
2nd, 3rd, or 4th natural frequency (overtone) and not for the
particular fundamental
that's
actually present (but not heard very well). In such a case, an end strike
brings up the levels of fundamental and lower overtones which can suddenly
cause difficulty in perception of the actual musical note one is trying to
enhance from some higher natural frequency (back to the brain's fuzzy logic
thing - lol). So, in tubes which have been cut for tuning at anything other
than the fundamental, I'd recommend always using a middle strike.
I've pretty
much given up on tuning to 2nd, 3rd, or 4th natural frequencies because there
are usually terribly unexpected results which pop up to spoil the stew if one
isn't very lucky. Instead, I select the particular octave(s) for which I wish
to build a set of chimes, then use Chuck's Calculator only for the "First
Natural Frequency" (fundamental) to select the "ideal" length/OD
for each note I wish to produce. More often than not, a tube with ideal length/OD
parameters for the first natural frequency, seems to sound very good when
struck either in the middle or at the end because the higher overtones seldom
sustain enough audible level to create much of a perceived difference in
musical note. However, the middle strike on such a tube still seems to give the
purest sounding note while the end strike is still richer, louder, and fuller
in sound - but perhaps a bit less "pure" in precise musical note.
Brent
From:
"Brent" <bmh1944@yahoo.com>
Subject: Re: Dumb Simple
Hey
Howard;
You've
asked a tough question for me to answer because, while I always do things
pretty "dumb", I have a terrible problem in keeping them
"simple". There's probably everything you need in the
"Links" section (to the left of this screen) - click on it - that's
the simple part. If you're not already educated on the basics yet, go to Jim
Haworth's "Article On Making
Windchimes"
first. If you're already up to our level of confusion in the basics, then go to
"Chuck's Chimes" to get all the rest.
If you are
simply looking for measurements of the chime set's individual components, suspension
technique, and design of a nice practical arrangement, then explore Chuck's
different tuned sets that are listed on his website - you'll find dimensions
and practical drawings that cover everything in a very simple and easy to
follow manner.
Your major
obstacle on the "simple" trail is deciding whether to tune your
chimes or not. Any Euler-based calculator will give you lengths for various
metals, OD's, and wall thicknesses which cover all desired frequencies from the
C1 to C9 range in pitch (octave). While those components mathematically and
physically will be present at any particular tube length, they do not represent
the respective amplitudes or the sustain/decay rates of all frequency
components present - nor do they predict how the mixture of those various
amplitudes will be received by the human ear and perceived by the brain's fuzzy
logic process.
There's two
ways of keeping the tuning process simple:
Don't tune them at all. Pick
some length you want the longest tube to be; use the charts or calculator's to
figure the different "notes" you want; cut the tubes; and don't worry
about tuning. You'll get a chime sound (rich in non-harmonic overtones), and
each tube will have some degree of different "pitch" compared to the
others in the set.
(2) Forget
any desired length you may have in mind. Use Chuck's calculator (on his
website) and plug in the type of metal you have, the OD, the ID (OD minus twice
the wall thickness); figure the ideal length for the "First Natural
Frequency"; make sure the "ideal length" box is checked; then
click "evaluate" and go with what you see - works every time and
gives great tuned results.
Since
you've already got some 1"OD Type-L copper with a nominal wall thickness
of .050", Chuck's calculator says your optimum tuning is going to be from
Ab/5 (831 Hz) to Eb/6 (1245 Hz). However, I've found you can go up or down a
few steps from the "ideal length" and still achieve a good success in
tuning. So, you can expand that a little to get a full octave (from which to
pick your desired notes or chord) that ranges from F#/5 (740 Hz) to F/6 (1397
Hz) with tube lengths
running
from about 11" to 15".
I've found
the "simple" method of tuning is to follow the above criteria because
it is the same observed method used by makers of premier windchimes and
expensive orchestra chimes. Simply stated, you can't produce the full spectrum
of highly audible tone (to the human ear) from the same OD of tubing. Very high
notes will be from 1/4" OD tubing at 4" in length, and very low notes
will require 6"OD tubing at 8-10 feet in length. So, use the tubing you
have with Chuck's calculator to find where it will be the most happy and
simplest to tune if that's your choice. Brent
From: hockinfinger@yahoo.com
Subject: Re: Dumb Simple
Howard,
I happen to
like dumb simple. I also like to work with whatever materials I happen to have
on hand. Most chime builders believe in trying to tune to specific notes, I
believe in relative tuning.
Here is my
dumb simple solution. If you are not concerned that this set of chimes is in
tune with another set of chimes, then I advocate relative tuning. Use the
longest tube as a basis to calculate the rest. Assuming the longest tube is
36", then multiply this by the following ratios and cut to those lengths:
x 0.944 =
34"
x 0.891 =
32-1/16"
x 0.817 =
29-7/16"
x 0.771 =
27-3/4"
x 0.707 =
25-7/16"
Assuming
you are using the same diameter pipe throughout, your result will be a set
tuned to a pentatonic major scale. This scale will be tuned relative to the
longest tube, but not necessarily to a particular note frequency standard. The
chime set should be in tune with itself, much like a guitar can be in tune with
itself and be completely out of tune with another guitar.
It may be
dumb, but it's simple too.
From: hockinfinger@yahoo.com
Subject: Re: Dumb Simple
These
ratios apply only if your pipe material, diameter and thickness remain the same
for all 6 chimes. If you want to mix and match different types of tubing, I'd
suggest Chuck's chimes page.
My
"Fantastic Scale Picker" spreadsheet uses VBA macros to calculate the
scales. You must have macros enabled for it to work. In Excel, go to
Tools>Options>Security and see what your macros security is set to. If it
is set to "high", the macros will not work. "Medium"
security will prompt you with a question, like "do you really want to run
macros?" Once you've changed the settings, you will probably need to restart
Excel. If you are viewing the spreadsheet in your browser,
you may
need to restart your browser too, but don't quote me on that. Then select the
key you want in column B under "Select a key here" by placing the
cursor on the desired key. Columns D thru L will change to spell each scale
based on the key you choose. For example, place the cursor on the cell in
column B labeled "F" and all columns D-L should change to show all of
the listed scales based on F.
I'm working
on an updated version of this. It has a second page which picks chords and
extensions in the same manner. Marty
From: hockinfinger@yahoo.com
Subject: Re: Dumb Simple
To
clarify my answer to the question of material and diameter: Yes, these ratios
do apply regardless of material or diameter. As long as you use the same
material, diameter and thickness of pipe for all 6 chimes, you can use these
ratios.
> Do
these ratios hold regardless of tube material - copper, EMT, steel, etc.?
>
> Ditto
diameter?
From:
"Brent" <bmh1944@yahoo.com>
Subject: Re: The Reality of Tuning?
Howard;
I
think it sounds like you've done your homework, read all the different areas of
advice, and managed to do a very good job with your first efforts. Whether
planned or not, you followed the three cardinal rules for getting close to what
you expect in the way of tuning a tube:
1. BEST
predictable success is usually obtained by using Chuck's calculator for the
FIRST natural frequency, and keeping within the "ideal" range of the
particular metal's length/OD ratios (usually from about 20:1 and 15:1) that are
listed for any desired frequency. However, I've found you can fudge a little by
going 3 or 4 chromatic steps above and below the "ideal" range and
still get pretty good results.
2. ALWAYS
try to use tubing from the same stock. Doesn't matter if it's the same
manufacturer and retail/wholesale store; try to find tubing sections with the
same "lot or batch" number printed or stamped on them.
3. ALWAYS
cut the tube a little longer than calculations indicate. You can always make it
shorter, but can't make it longer.
All of the
length/OD/wall-thickness/frequency calculators are primarily based on Euler's
mathematical/physics theorems which correctly compute the actual physical
properties which exist in a vibrating tube or rod at "resonance".
Unfortunately, those theorems do not address the relative amplitude levels of
each frequency component present, they do not take into consideration the
influencing physical effects exerted against a hollow tube's walls by the
internal air-
column
movement, and they do not address how the brain will interpret the
"package" of different existing frequencies at different relative
amplitudes with each other. Chuck's calculator has refined the Euler theorems
to include the internal air-column's affect and find those "ideal"
lengths where the air-column's movement is in phase (helping) the tube's major
transverse mode instead of impeding it.
The major
ingredient in any Euler-based calculator is the speed at which a physically
moving energy wave can move through a particular medium ("speed of
sound" through a particular metal); but the actual "speed of
sound" is going to vary with the actual metal composition of the tubing.
Copper tubing is probably more predictable because it is all about 99.9% pure
copper. "Hard" copper is mechanically hardened when
"annealed" (soft copper) of a larger diameter is drawn through a
sizing die that compresses it to a smaller OD/ID with a bit thicker wall from
the compression process of the sizing die - thus, becoming "drawn"
tubing. Steel EMT conduit is an iron alloy, and most aluminum tubing is also an
alloy because pure
aluminum is
as soft as lead.
The ASTM
(American Society for Testing and Materials) standards for copper plumbing tube
and steel EMT conduit are usually "fudged" by most manufacturers to
ensure even a poor lot or batch will still pass the standards. As a result,
there can be a variance in EMT alloy composition, and slight variances in wall thickness
of both copper tube and steel conduit. Any variance in alloy composition will
affect the "speed of sound" through the material, and a slight
variance in OD/ID/wall thickness (between different manufactured lots) will
also produce changes in Euler's mathematical calculations. So, it should be
understood that all calculators can only give a "ballpark" figure
based on some "norm" for copper, steel, and aluminum because ASTM
standards for "common grade" industrial tubing are only minimum
standards and do not particularly reflect the actual properties of the
material.
Bottom line
is to follow the major rules, then always cut the tube a little longer than
calculated because the calculators cannot be an exact science when the
exactness of the material being used is a variable. Brent
From: hockinfinger@yahoo.com
Subject: Re: The Reality of Tuning?
You
are not as crazy as you think. I've found that different brands of tubing have
slightly different sound characteristics. In my travels through chime world,
I've noticed that ANY additional mass on the end of a tube will make it tuned
flat. Even small burrs can tend to make it register a little flat. Temperature
can change the pitch.
If you have
just finished grinding, a hot pipe will be sharper than when it is cold. I like
to clean any ragged cut edges of a pipe before I analyze its frequency.
If I make
chimes from all the same size tubing (which I usually do) I cut my longest one
and tune it first. Then I use the L2 = L1 x (sq rt of F1/F2) method to achieve
the remaining lengths. Since tubing does not have even harmonics, a slight
mistuning of a few hertz is not noticeable to most humans (and some chime
builders) and is probably not worth pulling out your hair. I do try to keep
lengths near Chuck's ideal length when possible.
I have
never used copper for chimes, as I really don't like the sound of it. I always
have access to scrap EMT, so that is my weapon of choice. Aluminum is
expensive, but I think it is probably the best choice for really good sounding
chimes.
I also use
a spreadsheet, which calculates lengths based on frequencies, material and
OD/ID. This spreadsheet has a place for a "correction factor". I like
to tune one tube, adjust the correction factor to match my tube, and then use
the same factor to calculate the remaining tubes. This usually gets me really
close to correct tuning.
I honestly
do not believe there is any way to achieve precision tuning by cutting to
calculated lengths. There are still too many little factors which all require
adjustment. You'll need a micrometer, which is capable of measuring the entire
length of the tube, a humidity-free temperature-controlled environment, and
tubing, which is free of any foreign substances, including oxidation.On a
positive note, your measurements of 36.9cm and 52.4cm form almost a perfect
octave ratio (with less than 0.5% error) so you should trust your measurements
and be confident that they will work for you. You must realize that if Chuck's
calculations for one pipe are slightly flat for the pipe you are using, then
it's likely the entire range of measurements will be flat by proportionally the
same amount.
Chuck's
calculations are not wrong and your measurements are not wrong...it's the
stupid pipe! Marty
From:
"Brent" <bmh1944@yahoo.com>
Subject: Re: The Reality of Tuning?
Howard;
Marty
reinforced my earlier, lengthy response about tuning. While the math IS
correct, it can't possibly consider all the material variables and inconsistencies,
the degree of internal air-column influence as wall thickness varies, or
address the "perceived" results when the human ear's poor frequency
response is combined with the brain's fuzzy logic process (that's used to
interpolate a mixed stew of non-harmonious frequencies at different respective
amplitudes). Bottom line is cut 'em a little long and make yourself as crazy as
you wish with precise tuning.
I've
already explained the differences I've noticed in sound produced (and
sustained) by copper, aluminum, and steel; so one's "weapon of
choice" would depend on one's personal preferences. I prefer the very low,
very mellow sound from a deep-toned set of long, large diameter tubes. When
looking at what's best for such very low tones (C1 to C3 range) with the least
amount of high frequencies present, I'll stand toe-to-toe with anyone who
thinks aluminum or steel is better at
producing
and sustaining such than thick-walled hard copper or brass. For frequencies
above the C3 range, steel is the absolute best; but I don't care for the
"galvanized look", nor do I care for the galvanized look being
augmented by rust eventually streaming down from the node holes. Steel was once
good for me to play with because it was cheaper than anything else, but that's
rapidly changing to the point that it's becoming almost as pricey as copper or
aluminum-unless, like Marty, you have a good source for used or surplus EMT.
As per your
question about spending $100 on my choice of metal tubing, it would depend on
what I was wanting as a result. If I were going for the average mid-range
frequency tuning, best overall appearance, excellent produced sound, and low/no
maintenance, I would blow the bankroll on drawn, thick-walled, aluminum.
Your
question about tuning to the 4th harmonic is a moot point because there are NO
harmonics in a node-suspended tube or rod; instead, there are produced only
non-harmonic "overtones" that are neither multiples of the
fundamental or any other higher "natural frequency" (overtone). I
know that all the calculators, charts, and spreadsheets give length/OD
information to derive any fundamental (or higher natural frequency) from any OD
of tubing; but relying on that concept will definitely result in the high
alcohol consumption, frustration, dog kicking, and tool throwing. If you're
researching back into old postings, you'll find that most people who suddenly
find missing overtones, errors in predicted mathematical results vs.
perceived
sound, and other tuning frustrations will always stem from trying to tune at a
frequency higher than the FIRST natural frequency that's derived from Chuck's
"ideal range" calculator. Any "tuning" for a higher natural
frequency (overtone) means your tube will be longer because it is cut to be
resonant at some lower, non-harmonious fundamental (first natural frequency)
that will produce the desired overtone. The higher in natural frequencies for
which you try tuning,
the more
lower natural frequencies will be present - which, in turn, only adds more
potential problems for "perceived" results.
Your
question about doing a "quickie" set of chimes is very simple to
answer; you FORGET about tuning anything!! Our wonderful site attracts mentally
deficient, obsessive/compulsive people like me who seem to strive for some
degree of predictability, perfection, precise tuning, and musical harmony. OK,
lets get real in understanding that 98% of the people on this planet wouldn't
know a major scale, minor scale, pentatonic scale, 7th chord, 9th chord, or
progressive diminished chord if all of them cumulatively jumped up and bit them
on the ass - LOL. I've made a number of "chime quickies" from
whatever I had laying around by: observing Chuck's "ideal" first
natural frequency tuning criteria for the particular metal and OD, cut the
tubes for a couple of inches in length variation, suspended them properly -
then had Aunt Bessie compelled to go change her Depends because she was so
thrilled at the simple aesthetics of beautiful, diverse ringing sounds that had
absolutely no respective musical or harmonic correlation whatsoever. Go figure?
Brent
From: Howard
Russell <harusse@attglobal.net>
Subject: Re: The Reality of Tuning?
Well,
if cut and tuned the other four pipes this evening and it's exactly as you say
below. Since I had cut the 440 and the 880 pipes, I used the L2/L1 calculation
coming from both sizes and got really close on the predicted length of each of
the middle pipes. Once I had the predicted calculations, the process went
really quite quickly. I cut a couple of mm longer that the average predicted
length then worked them down to the in tuned length in just a couple of trips
to the grinder.
The 1"
belt sander along with a couple of marks on the pipe showing you how much
you've removed works great. I only needed to hit the belt sander to grind down
to the tuned length (according to my electronic chronograph guitar tuner) four
or five times per pipe. One was a bit fussy and needed a bit more TLC, but it
wasn't a big deal.
Also like
you say below, copper isn't all that great of a sound. However, it's a great
place to try your first set of wind chimes. This set will make a great gift to
my brother, a retired Navy gunnery officer who's spent too much time marveling
at the sound of exploding armament. Next is some Aluminum.
So, what
sizes and wall thickness' do you find work well in Aluminum?? Howard
From: "Brent"
<bmh1944@yahoo.com>
Subject: Re: Beginners beginning
I'm
assuming your "L1" tubing refers to Type-L hard copper? If you are a
beginner who's already read through enough to figure incremental tuning and
know where to locate your node holes, I would still suggest going to Chuck's
Chimes in the "links" section and going through his good information
first - because you will get even more insight. Don't give up if you get
confused because you need only to click on his Frequency/Length calculator,
choose the metal type, enter your tubing's OD and ID, then figure the
"ideal" range of lengths ONLY for the First Natural Frequency
(especially if you are a beginner) - you can't go wrong with that.
Most
calculators will all tell you some length of any tubing to get any fundamental
frequency (first natural frequency) you want; but don't count on actually hearing
it. A quick note on copper plumbing tube is that everything from 1/2"OD to
8"OD will ALL be exactly 1/8" (.125") larger in OD than its
stated size; so your 3/4"OD copper tube (with .045 wall thickness) will
actually be .875"OD and .785"ID for more precise figuring. If you
plug your tube's figures into Chuck's calculator, you will see the
"ideal" range falls much higher than the 440Hz you desire; instead,
the best range for that tubing will be
from 5B
(988Hz @ 12-5/16") and 6F (1397Hz @ 10-5/16"). Changing OD/ID figures
and recalculating will show that 2"OD copper will fall into the
"ideal" range you desire from 4G (392Hz @ 30-7/8") to 5C# (554Hz
@ 26").
By keeping
your tubing OD/length ratios in Chuck's "ideal" range for the first
natural frequency, you will more likely hear what you expect to hear with less
interference from non-harmonic overtones and other "gotchas" that
unexpectedly seem to pop up in tuning. Brent
From:
"Brent" <bmh1944@yahoo.com>
Subject: Re: OD, Length, Frequency Mystery
I've
tried to keep the OD/length/frequency relationship very simple so I can
remember it:
(1)
Fundamental frequency and tube OD are directly proportional in the fact that,
with tubes of the SAME length, resonant frequency increases as tube OD
increases - and vice-versa.
(2) When
tubes of different ODs are tuned to the EXACT same fundamental frequency, tube
length increases as the OD increases.
(3) So,
when tubes of different ODs are tuned to the SAME resonant fundamental
frequency, the larger the OD, the longer its length.
My
primitive experiments (only with thin walled tubing) have proven Chuck's
"ideal length" calculator (at any natural frequency) is correct in
aligning the internal air column's crossover points with those of the tube's
particular natural frequency transverse mode to which tuning is being sought.
There is a definite and noticeable degenerative change in sustained tone length
when the internal air-column's movement is restricted by internal objects (like
my jingle-
tubes), and
sometimes greatly enhanced by end-capping the tube. However, while
experimenting with "chimezilla" (which had about a 3/16" wall
thickness), intrusive air-column impedances had no effect that I could either
perceive or measure to any appreciable degree.
Fred
Flintstone is a master of ignorance - but an experienced "genius"
with practicality, predictability, and probability of success/failure ratios.
Euler-based calculators ARE correct and DO indicate what will be present as a
fundamental frequency and related overtones in any OD tube of a given length
and wall thickness; BUT, they DO NOT give a predictable indication of relative
amplitudes of each frequency component present. What one hears or
"perceives" from any chime tube, bell, drum, or other percussion
instrument will be primarily dependent upon whatever frequency component has
the predominant highest amplitude in the produced spectrum - and, the
particular frequency component that IS predominant will primarily be determined
by the physical characterics of the device itself.
OK, Fred
Flintstone's translation: Compare what you hear from a big drum vs. little
drum, big bell vs. little bell, and big gun vs. little gun. When any of these
are struck (or fired), they all produce the same spectrum of fundamental
resonant frequencies and related overtones (if they were
"Euler-tuned" for the same) - but the lower frequencies will be
vastly predominant in amplitude (and sustained tone) in the larger devices -
while the higher frequency components will be
greatly
predominant in amplitude (and sustain longer) in the smaller devices. Thus, if
one uses Chuck's calculator for the FIRST natural frequency (and remains close
to the "ideal" OD/length for such), it will usually ensure the
highest predominant amplitude for the desired frequency, octave, and purest
perception of that which one seeks as a result. Brent
From: Howard Russell <harusse@attglobal.net>
Subject: Where is that 'sweet' spot on tubes?
Jim,
Check out
"Chuck's Chimes" in the Links section. You will see an excellent
discussion on the interplay of the fundamental frequencies and their associated
harmonics. Examine the FFT graphs closely and you will see that there is a
relationship between the length of a specific tube and how long it continues to
ring - it's "sustain" (to use the term associated with electric
guitars as well as bells.) If you read carefully, the ideal length is the point
where the fourth fundamental
frequency
is the same as the 5th fundamental of the air column. This is generally close
to a ratio of 19:1 for the length of the tube to the diameter of the air
column. When these two frequencies are the same, the tube will have it's
longest "sustain" or ringing time - your "sweet spot" so to
speak. For any given material with a given diameter and wall
thickness,
there is only one "Ideal length".
Now, go to
the length calculator in Chuck's Chimes. You will see in the input data you can
check a box calling for "Output lengths only near the ideal length."
What this gives you is a selection of tube lengths and their associated
frequencies where you will realize the most "sustain." You will also
note that the output from the calculation also gives at the top to the output,
the specific "ideal length" and its associated frequency. You will
notice as well that this frequency seldom is the same as any specific note - C#
for example. Rather, the ideal length usually falls somewhere between standard
note frequencies.
What this
means is that if you want to keep all your tubes near the ideal length for a
given set of notes, you will build your chime with lengths near the ideal
length. For a well engineered chime that optimizes the tube lengths to take
advantage of the ideal length, it would not be surprising to see 1 1/2", 1
1/4" and 1" tubes for example in a well engineered six or eight tube
chime. Howard
From: "Jack
Maegli" <jackmaegli@jvlnet.com>
Subject: Re: Where is that 'sweet' spot on tubes?
That
was Doug Cox from Australia with the cricket bat analogy for hitting the sweet
spot. The only thing is, his tubes were tuned for upper transverse modes (2nd
& 3rd) which complicates things. Remember, I am a simpleton that likes the
primary transverse, so I smack 'em dead center length at the antinode, which I
guess to answer Jim's question means tubes hung at a distance from the hanger so
the striker is at the length center of all. With a 22.4% node I am assuming you
are going for the primary transverse, right Jim? I have seen expensive chimes
sold by those that are more interested in making money than a pleasing sound as
well. I always figure equivalent hung primary transverse tube chimes come from
a Chinese sweatshop with the profit made by everyone but the folks building
'em. Jack
From: thomasfromca@webtv.net
I learned aboard
ship that galvanized needs to be pickled before painting. To do this you can
wipe it with vinegar or a solution of TSP(tri sodium phosphate). Tommie
From:
"Brent" <bmh1944@yahoo.com>
Subject: Re: Where is that 'sweet' spot on tubes?
My
head has frequently been a percussion instrument when I've frequently beat it
with a wall while trying to tune a tube
cut for the
4th natural frequency on many occasions.
I agree
with Howard in the concept that finding a predictable "sweet spot" is
more contingent upon keeping the tube's "ideal" length/OD ratio
(optimum 19:1) so its predominant, highest amplitude mode will be at the first
natural frequency. I always use Chuck's calculator to figure the "ideal
range" (usually from 15:1 to 20:1) for ONLY the first natural frequency.
If I already have a particular diameter and type of tubing, I use his
calculator to see what "ideal" frequency range it's best suited for
at the first natural frequency. If I wish to build something in a particular
frequency range, I experiment with plugging in different ODs to the calculator
until I get in the "ideal" range I am seeking for the first natural
frequency. When you have a tube that's optimized for the first natural
frequency, it will usually produce that frequency as predominant over the
overtones regardless of where you strike it. When you have a very long tube
that's been tuned to favor a higher overtone, striking the tube at different
spots will usually cause different frequencies to be predominant at each impact
point.
I also
agree with Jack's thoughts on comparing a tube's "sweet spot" with
that of a ball bat or cricket paddle. There are different modes at work between
a ball bat and a resonant tube; and neither the bat or paddle is totally
consistent in OD and/or cross-sectional area along it's entire length like that
of a tube's uniform construction.
The major
difference between any bat, paddle, golf club, etc. is the fact that all of
them have a forced transverse fundamental node at one end (in one's hands) and
only one fundamental transverse antinode at the other end - where a chime tube
has three antinodes (both ends and middle) and two nodes; so any "sweet
spot" on a ball bat would not equate to the same spot on a freely
suspended resonant tube.
NOTE: There
is an exception to the "single antinode" rule when striking something
with a ball bat out of it's "sweet spot" range; in such an event,
there will be a forced antinode at the end in your hands which will be
remembered for some time to come - LOL.
Jack is
right in the fact that you can't go too wrong with a center strike as an
overall good place to start and/or to stay with. When I spent a lot of
frustrating hours experimenting with very long tubes (with length/OD ratios far
exceeding 40:1) to favor some higher overtone, there was a major difference in
component frequency amplitudes created by different strike points. A center
strike on such a long tube seemed to be much better for predominant higher
overtones while an end strike seemed to excite the fundamental and lower
overtones considerably more; the end strike gave a louder, fuller sound, but
was rich in all overtones and difficult to "perceive" some particular
musical note. Chuck may try out the ball bat theory on me, but I would think
that a very long tube (cut to tuned at some higher overtone) would have a
"sweet spot" when struck at any calculated antinode point (other than
the end or middle of the tube) for the particular overtone desired.
Since I've
exclusively gone to building nothing but first natural frequency chimes in the
"ideal" length/OD ratios for the octave I desire to produce, I've
almost exclusively suspended them for an end strike. I had the pleasure of
listening to a very good symphony orchestra a few months ago, and I paid
particular attention (naturally) to watching the lady playing a very large set
of "first natural frequency" orchestra chimes that were ranging from
about 1/2"OD to 5"OD, capped, end-suspended brass tubes. When she was
only adding "accompaniment", she would gently strike the upper capped
ends for a mellow, low volume, less-sustained tone. When she had notes to be a
little more predominately heard, she was striking the tubes near the middle.
Yet, when she had a major set of notes to emphasize, she gave them a sound
whack near the lower ends. Brent
Hi
Bill;
Maybe you
didn't get an answer to the earlier question because it sounded like you were
planning on making the chime tubes themselves out of wood like some bamboo
"windthuds" do; and there's no real way of tuning wood to anything
more than a different pitched clunk.
If you're
using 1/2" diameter, Type-M copper, you're already in hot water because
the wall thickness of Type-M is too thin to really produce much of a sound, and
1/2"OD copper isn't very good in any wall thickness. If you want to use
copper, I would suggest 3/4" Type-L hard copper as a bare minimum with
1" being better. Be sure you get the rigid "hard" copper which
is drawn tubing because the softer annealed copper that comes in a roll is only
"windthud" material and not worth considering at all.
Whatever
you decide to use, simply click on the "Links" section to the left of
this screen, and go to "Chuck's Chimes". You will not only find the
answers to many questions you haven't thought of yet, but click on his
"length and frequency calculator" to find all the lengths that will
best suit the tubing you choose. Simply enter in the outside diameter (all
copper is 1/8" or .125" larger than it's stated OD), the inside
diameter (OD minus 2 times the wall thickness), make sure the "ideal
length" box is checked, and calculate only for the "First Natural
Frequency". You will find the lengths listed that best suit the particular
metal, OD, and wall thickness of whatever tubing you decide to use. If you don't
have a
micrometer,
the wall thickness of most Type-L hard copper may vary from .045" to
.050" depending on the stock you select.
Brent
From:
"Brent" <bmh1944@yahoo.com>
Subject: Re: Windchime length formula simplification
The
simplified formulas (with or without a correction factor) let you start with
some tube of a given length and OD as a "base" point, then build upon
that length to derive related notes; these quickies sometimes work OK up to a
point, but they are as misleading in predictable results as the all inclusive
Euler-based length/frequency charts which abound for different metals, ODs, and
wall thickness.
Many get
confused by the fact that most frequency/length charts and simplified
note-building formulas lead you to believe that you can produce any note from
C1 to C9 range with any particular OD of tubing by simply cutting it to the
designated length. While the math is correct in indicating the particular
fundamental and related overtones that will be produced and physically exist in
any tube, they DO NOT predict the relative amplitudes of those produced
frequency components, nor do they take into consideration the terrible response
curve of the human ear and the brains "fuzzy logic" perception of
non-harmonic frequencies at varied amplitude levels.
Chuck (on
his website in the "links" section) has probably done more to refine
the Euler-based principles into a practical application than anyone has done
thus far. In a nutshell, Chuck's calculator is based on many factors which
determine an "ideal" range of length/OD ratios which will give a more
predictable degree of results to the human ear. Personally, I use only those
calculations to figure "ideal" lengths for the first natural
frequency because there are too many gotchas that suddenly pounce you when
using longer lengths for overtone tuning.
My personal
"shortcut" is to always keep a chime tube (regardless of metal, OD,
or wall thickness) tuned for the first natural frequency in an
"ideal" length/OD ratio that falls between 20:1 and 15:1 for almost
everything. If I have a particular octave in mind, I will use Chuck's
calculator (or a frequency/OD/length table) and select whatever OD is required
to stay within that "ideal" length/OD ratio range (for the first
natural frequency). If I've already got a supply
of some
particular OD of tubing, then I will build a set of chimes to whatever first
natural frequency range falls within those "ideal" length/OD ratios.
The
practical, real world proof of this basic concept as producing the best results
with respect to the human ear can be seen in bells, orchestra chimes, and pipe
organ tubes. Even though these three entities are totally different animals
with completely different physical fundamentals involved, they share a common
physical characteristic. High frequencies will be produced with narrow ODs and
short lengths; and as the produced frequency goes lower, OD and length BOTH
become greater down through the different octave ranges.
The bottom
line of practicality and predictability in what you will actually hear will be
centered around using short lengths of 1/2" OD tubing for very high
frequencies; but if you expect to hear a predominant tone down in the C2 to low
C3 range, you'd better grease up the credit card because you'll be using very
long tubes of 5" to 8" in diameter.
I don't
obsess with trying to tune down to the exact "text book" Hertz value
for any particular note. If one stays in the ideal length/OD ratio range, the
other tubes can be cut by using either the charts or quickie note-building
formula; then, only minor "tuning" will be required to get them in
tune with respect to each other. Brent
From:
"Brent" <bmh1944@yahoo.com>
Subject: Re: Marty and Relative Tuning
Jim
and Marty;
The
"higher modes" I was referring to earlier (when striking a metal tube
with another piece of metal) was along the same line as Chuck's thoughts where
those higher "modes" were overtones of the fundamental transverse
mode. As Chuck has wisely schooled us, the transverse mode is the linear
bending of the tube and the one which produces the major sound that is heard.
While there are other types of modes (axial, circular, cross-sectional, etc.)
also present and running in different directions, they seldom contribute much
to what is heard when the tube is struck. The transverse mode is actually a
general term because the fundamental and every associated overtone are all
transverse modes which are all present to some degree - just at different,
non-harmonic frequencies.
Another
"generality" is Fred Flintstone's "gotcha mode" which
includes all overtones that frequently are a major gotcha when you try tuning
for them - LOL. After much frustration with missing overtone anomalies, and the
brain's fuzzy logic suddenly not perceiving what your next tube cut is supposed
to be producing, I've chickened out to only working with the "ideal
range" figured for the "first" natural frequency when I'm
actually trying to tune a tube for some particular note. I only explore the
"gotcha mode" (higher transverse modes/overtones/natural frequencies)
when precise tuning is not an issue and I'm only looking to produce some
non-harmonious Aeolian sound.
I agree
that the musician almost always compels one to tune chimes in a
"chord" manner. I suppose various "scales" are good for the
random "Aeolian" effect; but since chimes seldom play a linear scale,
having all the various notes be part of a harmonious chord (of the same key) is
considerably more pleasant to the musical ear - but that's only my warped
opinion.
Tube cutters do leave a swedge and internal
burr, and the ding/tape/hacksaw process is no fun either; so, if you end up
getting the "disease", you'll probably be looking at a $250 ($180
rebuilt) Jet metal-cutting, chop-type band saw.
I totally
agree with Marty about the dementia of both music and chime construction as
being a condition which must be poorly nurtured to perfection with time and bad
experience - and not something as easily explained as a simple congenital
defect. Brent's excuse starts with playing the accordion since age 6. I wasn't
in the Marines, and have always wanted
to play a
sax; but I played an M-16 for a few years in the Army, ducked a few stray
bullets with someone else's name on them, and managed to fix a few pieces of
radio communications gear when I wasn't being shot at - LOL. The musical thing
has expanded to piano, organ, and synthesized keyboards; yet frequently, the
insane musical theory collides with the practicality of the communications
engineer to produce much conflict over choosing between perfection or artistic
license
(which, in most cases, are strange bedfellows). While playing the M-16 a lot
has reduced the hearing capacity and years of RF exposure have reduced the
mental capacity, the greatest dementia ingredient has resulted from my past 23
year career as a firefighter and hanging around the firehouse too long. Brent
From:
"bmh1944" <bmh1944@yahoo.com>
Subject: Re: New Windows application
Rick;
Thanks for
sharing your new program with us; it looks good, and I'll soon give it a try to
see how well it works out. I've used many good programs in the past to work as
a "general" guide to figuring the desired length of a particular
chime tube; but, so far, I haven't really found anything that works to any
precise degree with all metals, alloys, ODs, wall thickness, and degree of heat
temper (if any). My experience has seen that using a good "math"
formula works pretty well to a certain extent; and, after establishing a
"norm" tube and finding the right "correction factor" to
make the math agree with the actual perceived tone, one can use the same
material to let the math formula get them pretty close to deriving the other
desired
notes. But this only works to a fairly accurate degree when staying within the
same 13 note chromatic octave range with the other notes; I've found that, as
one extends further in octave ranges from the "norm" tube (the one
used to provide the right "correction factor" for the math), things
begin to go wrong - with the error becoming greater as octave separation from
the "norm tube" increases.
I don't
blame this on the "math", but simply feel the math hasn't gone deep
enough yet to cover the extreme complexity of what is really happening in a
hollow tube at mechanical resonance. While almost all resonant "tube
math" is based on Euler's established principles, Chuck has already found
the importance of the internal air-column's effect on the "mathematical
mechanical vibrations" of the tube. Chuck has come up with a way to figure
how to get the air-column's resonance to "agree" or be "in
phase" with the tube's linear fundamental mode to help sustain the effect
and the tone. Of course, there are many other modes of vibration going on in a
tube at the same time; and one would also think that not only the air-column's
effect to those modes, but also the ratio of tube's particular length to its OD
would also play a major role in what is actually being produced for human ear
"perception".
After doing
much online research, I found a couple orchestra chime sets, which spanned six
full chromatic octaves from C2 through C7. The most interesting aspect was
that, from deepest to highest, each octave of chime tubes was constructed from
a different OD and wall thickness of tempered brass tubing. The larger
diameter, thinner wall tubing was used for the lowest octave notes; and the
highest octave notes were of the narrowest diameter, thicker wall tubing. I
seemed to gather they had the "math" to support their arrangement and
choice of particular diameter and wall thickness for each octave; but, at
around $10,000 for a set of their chimes, I'd guess it would be easier to find
Jimmy Hoffa than it would be to get their math calculations. Brent
From:
"bmh1944" <bmh1944@yahoo.com>
Subject: Re: Adjustable Tuning
Marty;
We seem to
follow like paths in some things. I've been a musician for about... hmmm....OK,
let's say over 50 years (don't really want to give away my age - LOL). Among my
many synthesized keyboards, accordion, and concert grand piano, is my pride and
joy - a classic Rhodes piano that I still play very often and looks as good as
the day it was born about 45 years ago.
The first
thing to consider about the MAJOR difference between the properties of a freely
suspended resonant tube and the Rhodes, any piano, or any stringed instrument
is the fact of the different frequencies present. When a vibrating rod or
string is tightly and mechanically secured at one or both ends, the resonant
fundamental frequency is present along with EXACT multiples of that frequency
called "harmonics". Each harmonic above the fundamental frequency is
the exact same musical note, but one octave higher in pitch. A freely
suspended, mostly unrestrained tube or rod does not produce
harmonics;
instead, the various unrestrained vibration modes interact with each other to
produce "overtones" which are mathematically different multiplication
factors of the fundamental frequency and are usually not anywhere close to
being the same musically harmonic note.
The Rhodes
is a lot like the one-sided "harp" (or comb) of a grandfather clock's
chime rods; both are firmly attached to a fixed base at one end - so, they produce
musically agreeable fundamental and harmonic frequencies as a result. Even
though they are fixed at both ends, piano and guitar strings perform in the
same manner. While the particular metal composition of the string or rod will
affect the general timbre of the sound produced, the "speed of sound"
though those particular mediums does not affect the frequency of the note or
pitch. Since strings and Rhodes rods are fixed at one or both ends,
their
vibration is strictly in a lateral mode of moving back and forth from a fixed
axis at one or each end. Tightening or loosening the string and/or moving a
small weight along the Rhodes' rod does not change the speed of sound through
the medium, but DOES affect the frequency at which it laterally vibrates on the
fixed axis.
In a freely
suspended resonant tube or rod, there are no limiting factors to the various
vibration modes and non-musically
agreeable
"overtones" result. The vibration modes in the freely suspended tube
or rod ARE dependent on the speed of sound through the particular medium
(obviously, along with it's OD/length ratio as well). Adding a sliding form of
"weight ring" or other moveable device to a freely suspended tube
would be interesting to experiment around with, but I suspect it would only act
more as a dampening factor to some of the various modes or some of the resident
overtone amplitudes and decay/sustain rates. Changing those aspects may give a
different "perceived" note from the mix of musically non-agreeing
frequencies,
but I don't think it would do much to change the actual fundamental tuning.
From: cllsj
Subject: Re: Thanks Chuck
> I'm
sorry if my comparison between a stringed sheep and a tubular goat were
confusing, and I realize their produced resonant fundamental transverse
frequencies are contingent on different factors; but the comparison was only
done to show that both mediums would share the common property of producing
only one fundamental antinode, and that all higher frequencies would not only
be pure harmonics, but also that those harmonics would see resonance (at some
whole number multiple of their particular wavelength) in the same medium length
as the 1/2 wavelength of the fundamental sees resonance.
>
I'm
really having a hard time understanding what you are writing. Whether it is a
string or chime when it is excited ALL modes will respond. It is my
understanding that for stringed instruments that the higher modes are harmonics
of the fundamental. This is not the case for chimes.
> That
whole concept was based on the idea that any object being struck
generates/excites the entire spectrum of frequencies for a split second; but
only those frequencies which see resonance in the length of the particular
medium will sustain their vibration modes while the non-resonant frequencies
will almost instantly decay.
Again I
think if you used a solid rod you would see that the higher modes do not
"instantly decay".
So, my
thoughts:
> there
were that a fundamental and related harmonic frequencies are
"resident" leftovers from the initial strike excitation because they
see a resonant, low impedance environment that allows them to sustain.
While
higher modes in a solid rod will not instantly decay, they do require more
energy and therefore will decay more quickly than lower modes.
>
> My
ambiguous question (that you did not agree with) was really aimed at asking if
overtones in a free/free medium were being constantly produced by the three
antinodes of the fundamental mode (or something else) creating some kind of
regenerative "mix"? Not having a clue about the complex math
involved, it would seem that overtones would not see a resonant environment in
the medium length that's resonant to the fundamental because they are not
whole, even-number multiples of the fundamental. If such were the case, then
the overtones should quickly decay (in a non-resonant environment) after the
initial strike unless something was constantly generating them.
>
When you
excite the solid rod you have input some energy. The rod being an expert couch
potato wants to return to an unexcited state. Since it can't yell at its spouse
or have a beer, it vibrates to get ride of the energy. The fundamental uses the
least amount of energy so it vibrates at that frequency the longest. There no
complex math required. :) Besides I'm sure I don't understand all the math
either.
Going to
the next higher octave would be the original length times .707 and going to the
next lower octave would be the original length times 1.414 - yup, I can hear
the laughter now.
For a
solid rod the numbers work. However, one could end up outside the ideal length
for a tube and therefore may not produce the expected results. Chuck
From: cllsj
Subject: Re: Tuning brass tubes?
Brass is for the most part copper. So just select copper as the material in
my length calculator. Chuck
From:
"Brent" <bmh1944@yahoo.com>
Subject: Re: 7/8 Steel
Conduit. Attempt
Zcat;
As I warned earlier, the Korg tuner is assuming a "harmonic"
instrument, so it picks the most predominant frequency and gives you a reading.
Unfortunately, if your strike has excited one of the non-harmonic overtones to
a greater degree than
the fundamental, you will get an erroneous reading from the Korg.
Again, use something that you can trust as being "in tune" like a
little synthesized keyboard (pianos are notoriously out of tune), and use the
old ear-ball comparison to decide if you're pretty much in tune, a little
sharp, or a little flat. If you're sharp, you're screwed because you can't make
that tube longer, so recycle it for one of the shorter tubes. If the note is a
bit flat, only file off about 1/32" at the most before rechecking the
tuning each time.
The MOST IMPORTANT thing to remember is WHERE you strike the tube. Striking
the tube anywhere other than the exact middle of its length or at one end will
tend to excite the non-harmonic overtones a little more than the fundamental.
Usually, the best and purest note is achieved by a center strike. So, if you
are going to strike the tubes manually, it would be a good idea to find the exact
center of each tube, use a piece of masking tape as a guide, and draw a line
all the way around the tube with a magic marker - that will be your
"strike zone" for the best and most consistent note.
It is also wise to try your best to strike the tube with the same object
(preferably, hard wood, hard rubber, or hard plastic with a relatively sharp
edge), and try to strike the tube with the same amount of force each time. It
might not hurt to experiment a little with different materials used as a striker
to see which particular one seems to give the purest sounding note and most
consistent performance. Brent
From:
"Brent" <bmh1944@yahoo.com>
Subject: Chime Tube Tuning
This sounds like a good time for me to give my practical chime tuning
lecture again (to anyone really interested) in hopes that it may help anyone
who still labors in confusion about the differences between a
"harmonic" instrument, an "overtone" instrument, and any
electronic devices or computer programs which may be used as a tuning aid.
Being a musician, I realize that many people often confuse the major
difference between a "harmonic" and an "overtone". The
first thing to understand is that an "overtone" instrument or device
DOES NOT produce "harmonics", and a "harmonic" instrument
or device DOES NOT produce "overtones". The easiest way to understand
the basic differences is to look at any good spreadsheet (like Lee Hite's Excel
spreadsheet) where the entire range of musical notes and their respective
frequencies are listed in the down column - and their respective overtone
frequencies are listed beside each note in the
horizontal column. If you refer to such a chart, the following will be easy
to understand.
HARMONIC: Start with any note you choose (1C for instance) and look at its
fundamental natural frequency. Now look down the column to find 2C and note
that (except for very minor decimal difference) the fundamental frequency for
2C is almost exactly twice the frequency of 1C. Go on down to 3C and you will
note it is almost exactly twice the frequency of 2C. That same exact frequency
doubling goes on in the same manner throughout the list; and the 12
chromatic-note range between any musical note and the same note above or below
the original note is called an "octave" - e.g.: one
"octave" would be
between 1C and 2C, or 2C and 3C.
HARMONIC INSTRUMENT: The physical suspension/mounting properties of a
fixed/fixed string or fixed/free rod on any musical instrument, will make that
instrument a "harmonic" instrument with the fundamental transverse
mode (fundamental or first natural frequency) having only one antinode of maximum
vibration movement. This will almost always make the fundamental frequency
extremely higher in amplitude than the related harmonics which are also
produced. In either case, a fixed/fixed string or fixed/free rod will have a
resonant fundamental frequency (musical note) and ALL of the produced
"harmonic"
frequencies will be the same exact musical note as the fundamental, but at
higher octaves. That's why the longer string or rod has a "richer"
sound because there are more octaves of the same musical note being produced in
the human hearing range. The bottom line on a harmonic instrument is that ALL
produced frequencies will be the same exact musical note - just at different
octaves (or "pitch").
OVERTONE: Now look back at the spreadsheet and pick any musical note (I'll
just use 4C as an example). I won't get picky with exact numbers, but will
round them off to get the concept across. Look at 4C with a fundamental
frequency of 261Hz; the look across at each successive overtone and write down
its frequency. Now take each overtone frequency of 4C and go back to the first
vertical column of actual musical notes and find the musical note that's
closest to the frequency the produced overtone. Here's what you'll see:
Fundamental: 261Hz = 4C
1st Overtone: 1413Hz = 5F to 5F#
2nd Overtone: 2336Hz = 6F to 6F#
3rd Overtone: 2336Hz = 7D
4th Overtone: 3490Hz = 7A
You can see that this "overtone" instrument is NOT going to be
giving your ears (or any electronic tuner) a pure "C" note at
different octaves; instead you are going to be getting a mixture of 4C, 5F,
6F#, 7D, and 7A all at the same time. Now which particular musical
"note" from this jumble of non-harmonic frequencies do you think
you're going to hear?
OVERTONE INSTRUMENT: By it's free/free nature of suspension (suspended at
one or both naturally occurring nodes) a CHIME TUBE or ROD has three antinodes
of maximum fundamental mode vibration movement and becomes an
"OVERTONE" instrument as a result. The major difference with any
overtone instrument is that many different factors of widely varied length/OD
ratios and strike points can greatly vary the respective amplitudes of the
fundamental frequency and all resident overtones. So when these varied
amplitudes of all non-harmonic frequencies (different musical notes) get past the
terribly non-linear human hearing response and fed to the poor brain for some
sort of "perceived" musical note or tone, the brain's "fuzzy
logic" process uses those frequencies of the highest amplitude in it's
final calculation of what you actually "hear or perceive" as being
generated.
NOTE: This same process is also used by any electronic tuner that is
"assuming" you have a harmonic instrument - not an overtone
instrument. So, it will pick the highest amplitude frequency in the
"mix" and display that as your musical note. However, the tuner
doesn't take into consideration the terribly non-linear human ear frequency
response; but it doesn't have to because a harmonic instrument would be
producing the same musical note regardless of frequency. As a result, your
electronic tuner may be displaying a musical note that you don't really
perceive as being correct because it's homed in on a particular frequency that
may be higher amplitude on a purely liner basis, but (in reality) at very low
amplitude with
respect to the non-linear human ear response.
MOST PREDICTABLE TUNING OF A CHIME TUBE:
I'll sound like a broken record again, but this will cut through a lot of
frustration if you're not into experimenting.
1. USE CHUCK'S CALCULATOR - AND USE IT AT THE "IDEAL RANGE" FOR
THE "FIRST" NATURAL FREQUENCY!!! You can experiment with much longer
tubes tuned for higher natural frequencies, but that's where you will begin to
run into those occasional unexpected anomalies of missing overtones and/or a particular
length that suddenly produces a totally unpredictable "perceived"
musical note.
2. Don't try to use most spreadsheets and think you can produce any given
"perceived" musical note at any octave with the same OD of tubing.
Those frequencies will be there, but usually at such low and/or varied
amplitudes you won't hear them. If you desire some particular note at a given
octave, use Chuck's calculator at the "first" natural frequency and
start plugging in tube ODs until you get into the "ideal range" you
desire. That will almost always ensure the fundamental mode will be the highest
amplitude and most predominantly "perceived" out of the mix of
non-harmonic overtones.
3. Make sure you correctly measure your tubing's exact OD and ID. If you
figure the ID by correctly measuring the wall thickness with a good micrometer,
REMEMBER the ID will be the OD minus TWICE the wall thickness.
4. Last but not least, tune your tube BEFORE drilling any node mounting
holes because any change in length after the holes are drilled will NOT be the
correct node point for the new length. I've found the best way for tube tuning
is to horizontally suspend it from both nodes (.2242 x total tube length from
each end). Many of us use a good solid horizontal suspension bar (clamped
T-post, garage door railing, large wife with long outstretched arms, etc.) and
hang the tube with long loops of very fine monofilament line or a bunch of thin
rubber bands tied together. Always test strike the tube in the
center if you're looking for the best excitation of the fundamental mode
without over-exciting the overtone modes. Each time you remove any of the
tube's length to raise the fundamental frequency, always remeasure the node
points and change the suspension points to match.
5. Personally, I really like the freebie little "wtune" spectrum
analyzer program you can get from www.cipoo.net to do any exact tuning because
it is focused only on the 40Hz-4000Hz audio range that's more along the peak
range of human ear response. Even at that, you must take care in looking at
"linear" amplitudes because the human ear's response curve drops off
quite a bit below about 250Hz and above about 3500Hz (which, not surprisingly,
is the major range of the human speaking voice). Brent
From: "Brent" <bmh1944@yahoo.com>
Subject: Re: Chime Tube Tuning
Katie;
You're right in harmonics being more pleasant to the ear and less
frustrating to deal with. Unfortunately, a chime tube will NOT produce
harmonics under any means of cultivation, modification, or alcohol consumption.
Chime tubes are "overtone" devices whether we like it or not; so much
of our grief, discussions, frustrations, confusions, and shared advice to each
other all stems from the problems in dealing with overtones.
If you look to the left of your screen, you can click on the
"Links" section to find much information. Just click on one of the
following links located there for a lot better information than I can give:
1. "Making Wind Chimes" - A very good article by Jim Haworth for
anyone just getting into the hobby. It explains all the basics in an easy to
understand manner and is a great starting point.
2. "How To Make Wind Chimes" - This page gives you the link to
Lee Hite's different Excel spreadsheets. While they are extremely informative,
and very good reference material to download and keep handy, they are also one
of those things I warned about that lead some to believe they can produce any
good sounding musical note, at any octave, with any particular OD of tubing.
3. "Chuck's Chimes" - This goes considerably deeper into the
technical aspects for the more advanced folks. If you scroll down the first
page a little ways, Chuck has some underlined links for some very good, very
detailed windchime plans for those who want to get right into building
something that works very well. You will also see his underlined "Tube
Length/Frequency Calculator" link that you can click on to figure out the
best lengths for a particular type and OD of tubing.
As a musician myself, I totally concur with your thoughts about tuning a
chime because it is theoretically impossible to perfectly tune an overtone
device since none of the resident overtone frequencies are either musically
harmonic or exact octaves of each other like the resident frequencies of a
harmonic instrument. So, the best one can do is to (by calculation or dumb
luck) get one of the natural frequencies highly predominant in amplitude so the
brain will "perceive" a somewhat-musical note from the non-harmonic,
hodge- podge of produced frequencies that "kinda-sorta" sounds like
it's in tune with a harmonic instrument (damn, 20 yard penalty for too many
hyphens on the field). Brent
Links:
Making Wind Chimes by Jim Haworth
Windchimeconstruction
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information about wind chime making.
Updated 3-24-05