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Few industries have so many myths and downright misunderstandings
as the audio industry. I have skirted most of these and have,
of course, come to establish some opinions of my own. Not to
contradict the pure physical laws, which undoubtedly are the
best basis for a good understanding of this subject. And ladies
and gentlemen..... most things have been done before! Below,
I have outlined my opinion on some subjects I think maybe need
some clearing up.
This amp sounds much louder
than mine!
It is a common misunderstanding that the actual position of
the volume knob tell you anything about how much power you are
really pushing out! So, if you have a 50-watt amplifier it turns
out 25 watts when the knob indicator points straight up - right!
Wrong! Better to see the volume knob as a valve. If there is
no input it doesn't matter where the control is set. No input,
no output, no watts. The specifications of your amp should tell
you at what input level it turns out the rated power. This doesn't
necessarily mean that the volume has to be turned fully clock-wise
to achieve this. Or if it was so, a higher input would give you
much more than the rated power at full "volume".
That's why it is so very handy if you have level adjustments
on the various inputs - tuners, turntables, CD players and so
forth. This was quite common on early hi-fi/stereo equipment.
Of course, a compact system has all this built into the design
from the outset. So, when your buddy boasts of how much more
sound his amp puts out with the volume knob at almost zero, just
give him a grin - he knows naaathing. A watt is a watt!
For people in the business this can be a real problem. Some
just won't hear what you are saying about this phenomenon, but
is staring blindly at the volume knob totally convinced that
this a heck of an amp. Not understanding that maybe the amp is
working full blast already with the marker in the 12 o'clock
position and that after that there is only distortion and burnt-out
speakers. Back.
How many watts are these speakers?
The wattage of a loudspeaker tells you nothing about the actual
sound-quality of that speaker! Also, it will tell you little
about how much sound it puts out. The wattage figures should
always come together with the sensitivity rating. That will tell
you something of how much sound you can get out of it. I say
something because there are several parameters that come into
play here, too. But again, it says nothing about the actual sound
quality. Important to consider in this context is also the quality
of the amplifier. It is common knowledge that it is better with
a stronger amp that plays cleanly, than a weak amp that puts
out a distorted signal. Any amp can blow any speakers! Back
Listen to that bass!
Deep bass is a rare thing! A thumb-of-rule is that any good
sound system should be able to work in the frequency range of
20-20000 hz. Which, incidentally, also is considered to be the
approximate maximum range of the human ear. Very optimistic,
that is! This frequency range is no problem to duplicate in electronics
- harder in loudspeakers. However, it all starts in the recording
studio. When music is recorded and mixed the producers is faced
with a dilemma - for whom shall he produce? The general pop-music
listener or the serious hi-fi buff. Because, these categories
have different demands. It is also a financial aspect. Does deep
bass cost more to produce? Of course not - but "good"
music sells, and "good" music for the guy with the
ghettoblaster differs from what is "good" for the other
guy. If we say that deep, pumping bass sells, the producer needs
to record it so the buyer hears it. And a ghettoblaster does
not reproduce much below 100 hz. Alas, most recordings do not
have "real" bass. Very few recordings contain a significant
amount of frequencies below 50 hz. And does it matter? After
all, few instruments operate in this range. To reproduce deep
bass with any volume puts large strain on both power amplifiers
and speakers. Amplifiers can do it within their power range (volume)
- speakers have clear-cut limitations that is governed by physical
laws. Enough to say is - generally, deep bass in small cabinets
can be done, but usually demands much power. Large speakers/cabinets
can do it more easily, with less strain on the amplifier.
In the "vinyl age" there were other problems. A
bass note demands much more "space" on the actual record
and were therefore played down simply for space reasons. For
the same reasons the recording industries standardized on several
equalization curves to help out this problem. Also, many of the
turntable pick-up cartridges at that time had problems with reproducing
deep bass. Again, the producers had to cater for real-life considerations.
Today, the "vinyl" guys generally have the best of
equipment so this is not a major problem for them. But does it
help - most records were not produced for them.
Finally, the way we perceive frequencies varies with the sound
level. This has been standardised in the Fletcher-Munson law,
a curve that shows how our hearing is impaired by the actual
sound level. At low level we hear less of the deep and high notes.
If you feel there is little deep bass in your system, turn the
volume up! Or compensate with the tone controls. The "loudness"
functions on many amplifiers are constructed to compensate for
our hearing problems. However, these can seldom be completely
correct if the whole reproducing chain is not balanced to the
actual curve. For example, a high-sensitivity speaker will play
too loudly, and vice versa. Back
Analogue
sound is much superior to digital!
One of the real pains in the a.. when working with hi-fi was
the d..... vinyl records! And there wasn't much to choose from
when a proper set-up should be demonstrated. After all it was
made to reproduce the signals from records. There was noise and
distortion all over the place, crackling sounds and inherent
rumble. There was tape, of course, but those were usually recorded
off vinyl records, too - with the added niceties of tape hiss
and drop-outs. Commercial tapes had much of the problems that
cassettes had when they were first introduced - tape hiss, distortion,
drop-outs and poor frequency response. Tape also deteriorates,
as do vinyl records. The best sound material was actually FM
concert broadcastings. Also, recordings made by the broadcasting
companies as these were mint copies. However, such concerts were
seldom available during the day, or when the potential customer
suddenly fell in through the door.
So how do I like the digital media. I haven't played a vinyl
record since I first got my hand on a CD player! Except once
in a while to ascertain myself that I remember correctly. I do!
So what's the matter with the guys that renounce the CD world,
to wallow themselves in the blessings of the vinyl that I have
outlined above? I do not know!
But there are, as I started this page with, a lot of myth
and misunderstandings going around. What seems to have slipped
the mind of many of those who discuss music - and the way it
is reproduced, is: What should this excact recording really sound
like? How should it sound? Our references often decide our opinion
on that. We might have heard that music piece in a concert hall
with a different orchestra. That is our reference and that is
how we would like it to sound! Without even knowing it. But this
other orchestra cannot sound like that on recording made in a
studio. Played in your own living room!
So what has this got to do with analogue versus digital. That
very often we do not have our bearings corrected before we cast
off. It could be that you like vinyl the better because you are
used to that sound. It could be that you do not understand that
the digitals reveal problems during recordings and mixing better
than the analogue records do. And that doesn't sound nice! I
think it is much the same the case, the discussion tubes versus
transistors. Now, tubes I do like. Both because the negative
results are not so pronounced as with turntables and vinyl records,
but also because these old units work as good as they do. Vinyl
doesn't. And that is my solemn opinion. Back.
That
one sounds better!
Have your heard the story about the Danish audio reporter
who claimed that he could hear the difference between various
optical cables. Bets were made with his fellow reporters and
a listening system was set up. After a short while it was quite
obvious that he had lost the bet - he could not hear the difference.
Or could not tell what the differences were - it there was any
difference. Of course, there was no difference! Or rather, no
difference that the human ear could perceive! There was no logic
in the choices this reporter made, and in the end he had to admit
it. This trial was made by A/B-testing, and therefore it must
be correct. Must it not? Switching between two paralell sources
should give the best results when comparing different equipment,
right!
Maybe. Today I am not totally certain. When I first started
out in the audio business I was a rather headstrong young man,
with bastant opinions on different matters, particularly regarding
audio/hi-fi - I was quite convinced that I had something to contribute.
The good thing about working with a subject for a long time is
that one, unavoidably, learns about the subject - if you are
open-minded, that is. Also, when you are supposed to make your
living by it for a prolonged period you simply cannot be superficial
about it. Arnfinn, my partner, also had a very analytical mind
and together we soon came to draw a couple of conclusions that
often put us head-to-head with the hi-fi Gurus, as we liked to
call them. Firstly, we became much less firm in our opinions
regarding sound. This came after we had gone through a couple
of eye-opening experiences. Secondly, we found that most of the
Gurus seldom based their opinion on facts or scientific evidence,
or even considered to take such elementaries into their reasoning.
We, on our side found, as we matured, that there was usually
a connection between sound differences and technical measurements
- frequency response was often a major part of it. Thirdly, it
became clear to us that our hearing and perception of sound is
very much affected by both emotional and physical impressions.
Of course, we played, talked and lived by reproduced music all
day long, receiving inputs constantly. Our senses became very
keen to what I will call practical audio and the way different
people opinioned it. Because we heard so many opinions!
Of course, much of our efforts went into analyzing and promoting
the brands and products that we lived by. But we were in the
fortunate position that our very broad product spectre did not
make it necessary for us to prostitute ourselves. So - when some
shallow "expert" made light-hearted, maybe negative
remarks about some of our select items, we had great pleasures
in tearing his/theirs defenses apart! Trying, anyhow!
But to get back to where we started - is A/B listening the
ultimate way of comparing audio equipment. First let me say that,
quality-wise, there are other factors to consider in a unit than
the "pure" sound. Versatility, reliability and "looks"
are all important. "Looks" - can that be important
for the sound? You bet! That is why an A/B-listening test always
should be made with the actual units hidden to the listening
panel - blindfolded, so to speak. And it is very important that
the sound level does not change when switching. Louder is better!
To give a little example: When we imported our first McIntosh
products, one of those was a C28 preamp - a highly regarded product.
We made no delay in having it put to the test - it sounded marvelously.
And with that look it should! Exactly - the "looks".
After a couple of hours we A/B-tested it with Arnfinn's home-built
Dynaco PAT-4 preamp. We could not hear any difference! Of course,
there is nothing wrong with the PAT-4, other than it being a
cheap, less than pretty electronics kit. Anyway, not as pretty
as the C28. Now, such was our experience with many a McIntosh
unit, they were jewels to behold but sounded no better or worse
than any other similar units of some status. And why should they.
In all, we found that the difference in sound quality between
electronics of a certain standard, were minimal.
During a demonstration at a dealer in the city of Bergen I
brought with me the largest Rotel receiver - the RX1603. That
was a remarkable unit! Nominally, it was specified as 2x160 watts
into 8 ohms, both channels driven simultaneously. However, we
measured it to almost 2x250 watts at the specified maximum distortion!
Rotel had made it so that the power amp could be separated from
the tuner/preamp part with a special split kit. Quite practical,
as it measured something like 50 cm. deep. Anyway, this dealer
was a devoted fan of the Norwegian Electrocompaniet products,
which had just started to make an impact on the audio market
here. We were less than enthusiastic about the same - that went
both for the guys running the comany as well as the products
they turned out. Arnfinn characterized their insides as a "crows
nest".
Anyway, after a while this dealer had to admit - resisiting
violently at first - that sound-wise there really were no reason
to sell the Electrocompaniet units instead of the shiny Japanese-made
power-house - the Rotel RX-1603. With a tuner added the Electrocmpaniet
units would cost considerably more than the RX-1603 and you would
be stuck with a 20-watt amplifier instead of a 200-watter, which
gives you 10 decibels less sound, everything else being equal!
20 watts might be OK if you have some high-efficient horn speakers
- which the Gurus of course never could have. That would make
it too simple! In a context like this the Guru would always counter
by persisting that - in another environment, their champion
would be better. Elegantly ignoring that it might just as well
be the other way around! It is very hard to admit being wrong.
Which is only human. Good sound is, for a large part, in the
ear of the beholder. I.e. - what you yourself has decided! (The
good book of sound). Back.
Tubes are
much superior to transistors!
Here we have much the same problems as when comparing analogue/vinyl
with digital/CD's, and private opinions on what you would like
your reproduction chain to sound like. Tube enthusiasts will
often discard any transistor amplifier for any
tube amplifier, disregarding the myriad of factors that contribute
to good or bad sound in an amplfier.
The main reason for the decline of the tube electronics was
economic! Transistors were much cheaper to produce than tubes
and one could get rid of the very expensive (relatively) transformers.
The first transistor models were both noisier and less reliable
than the established tube constructions. There was more noise
in the first transistors (germanium) and often not enough performance
margins were built in. The power race was on and many manufacturers
pushed their designs to the limit, resulting in unstable and
temperature-sensitive constructions
It is said that tube distortion is subjectively less annoying
than transistor distortion. For the same reason tube amps yield
more "music power" before the distortion gets unbearable.
Also, it is generally aggreed that tube amps are superior in
the mid-range, but can lack punch in the lower frequency area,
and are not as subtle in the top as good transistor amps.
While there is a good reason why tube amps can be inferior
in the bass area - namely cheap output transformers, there is
very little reason why they should not give excellent treble
performance. Of course, in the forties and the beginning of the
fifities, one was not very keen on high frequencies at all, simply
because the sources were inferior and added much noise and distortion
in that area. For that reason the upper frequency range was limited
on purpose.
So why do tube amps perform so well in the mid-range? Or do
they at all? Could it not be that it only sounds like that because
there is less bass and treble, and that we like? Or the simple
fact that most of the signals are in the mid-range - for acoustical
instruments, anyway. Or that they sound laid-back because we
are used to transistor-amps that are more pronounced in the bottom
and top. Or do we think they sound better because of their "looks".
Have you ever had a romantic evening with the lights dampened
and your tube electronics glowing undiscreetly in the bookshelf?
I have! I loved my McIntosh MX-110 and MC225 to the degree that
I sold them because I thought it sacrilege to let my partner
play popular FM-music all day on them. So out they went together
with my Infinity RS 2.5's! If only I had stowed them in the basement
instead of selling them.
Talking about bass. I found that the 25-watt MAC performed
better as a bass amp with my bi-amped Infinitys than my 50 watt
AudioResearch tube amp, which had a rather "flobby"
low-range but a superior midrange. Which proves that the difference
within the different amp categories are just as large as between
the categories themselves. So, was it that the MAC had better
transformers than the Audio research amp, or was it just a difference
in frequency response? Or was it that the Audio research was
perceived as much better in the midrange when I let another amplifier
take care of its weak point? If it was a weak point. Maybe it
was just my Infinitys that needed to be adjusted down a little
- in that room - and that the MAC did it.
I don't think that tube amps, generally, sound better than
good transistor amps, but they are much more fun to own and use!
Tube amps are tradition and culture in one. And that's a fact!
Back.
My amp yields 600 watts - brochure
says so!
The wattage (voltage, actually) of an amplifier is important
both to the seller as well as the buyer/user. For the seller
- because wattage sells! For the user - to drive his loudspeakers
to the sound levels he wants!
First, one fact should be underlined very strongly- the correct
way to go if you want to achieve higher sound levels - is to
look for higher-efficiency speakers.
There are many ways to specify amplifier wattage (power) -
from very conservative, down-to earth standards to highly exaggerated,
fantasy figures. If you look at how car amplifiers are specified
today you get an idea of how it once was in the hi-fi industry.
In the "tube era" there were mainly two ways to specify
amplifier "power" - RMS and "music power".
RMS (Root Mean Square) is the power an amp can yield for a longer
period, within a given bandwith (frequency range) at a specified
distortion level. "Music" power is its ability to handle
short "bursts" of signals, often at a higher distortion
level. When stereo came to light it became quite common to add
the two channels, so as to quote "total" power. But
there was more.
When Arnfinn and I started out we right away decided that
for us there was only one way to quote the "power"
of our products: Continuous (RMS), full-range (20-20khz) wattage
in 8 ohms, both channels driven simultaneously, at a specified
distortion level. In 1970 when we started to look for U.S.-made
brands to import into Norway the power-race was at its highest
peak in the U.S.. We started a crusade for realistic parameters
to work after in "our" market. This was not taken completely
out of the air, but based on the DIN 45500 standard and the American
IHF-standard. (IHF= Institute of High Fidelity). While the DIN-standard
worked in 4 ohms, the IHF-standard was quite down-to earth, using
8 ohms impedance, even if they set 1khz as the measuring point
for power/distortion. After that the manufacturers started to
quote full-range, as well.
An example of how a power rating can be inflated: An amplifier
giving 20 watts per channel measured with "our" standard
would increase to 40 by adding the two channels. One would then
quote it in 4 ohms, adding maybe 50% = 60 watts (OK if the power
supply can handle it). Instead of measuring full-range one could
measure it at 1khz, where distortion is lower at a given rating.
Result: 80 watts. Measuring at higher distortion levels, without
talking too much about it would give you 100 watts. Measuring
one channel at a time would give you 120 watts - not mentioning
that you already have summed the channels. One channel at a time
give you better numbers because the power supply only need to
take care of one channel at a time. So, voila - the 20-watt amplifier
has become a 120-watts amp! Same "system" with a basic
100-watt amp. would give you 600 watts. A lot of amp for the
money! And this is even before you have started talking "music"
power, making power additions to suit your own taste.
Just as wattage in a loudspeaker tell you nothing about its
sound qualities, much the same goes for amplifiers. However,
it often is some relevance because when designing and manufacturing
high-power amplifiers you might as well consider sound quality
at the same time. There is usually a connection, but not always.
That is not to say that a low-powered amplifier cannot have excellent
sound qualities. However, this quality will also cost some and
the manufacturer is then left with an expensive, low-powered
amp - which is not good for business. Get my point?
To take a step backwards - the "music power" quotation
do have some justification. Music is, after all, not continuous,
steady-state signals - but a complex variety of ever-changing
combinations of frequency and levels. Problem is that any other
than the "continous" specifications are so hard to
quantify. There are no good general standards for it. Therefore,
when you know the "continuous" rating for your amplifier
you know you have some margins! And that's a fact! Back.
So you
believe in Monster Cable!
The cable hysteria started at the beginning of the seventies
and it came as a total surprise to us. Simply because we had
never felt any need for more than the regular lamp cords as speaker
cables. More and more people came around, asking for, and discussing
the merits of various cables. Monster Cable was most often mentioned.
It was obvious where this trend had originated locally - in the
same circles denouncing the merits of horn speakers (they "colour"
the sound) and "transformer"-equipped Mac's. (Their
mission differed totally from the regular trannies found in tube
amps). As it were, we became very sceptical - as we saw it little
sense had come forth from the above-mentioned group till then.
Alas, we were never able to find that the various "fancy"
cables made any improvements on the sound. Not to our hearing,
anyway. Of course, at extreme speaker cable lengths, dimensions
should be increased. But no need for specialised leads. Heavier
lamp cord simply did the trick. We had a hard time convincing
the listeners in our show room that they should forget about
cables and listen to the music! Often to no avail. This was the
"trannie and horn" - syndrome all over again.
It was very interesting for me, a little while ago, to read
about one who had exactly the same problems in his time. Namely
the highly respected Roger Russell, the person who built up the
speaker production at the McIntosh factory. His experience was
the same as ours. However, with the extensive resources available
to him and his people, they did extensive research on this matter.
Their conclusion was as ours. Bullshit! (He doesn't use that
word - we did) In the end Mr. Russell had to acquire some fancy
cables to the factory showroom to make the customers concentrate
on the real thing: The McIntosh Sound! And this happened in just
about the same period. So, somebody made a lot of money for nothing!
Beware, the audio business in general believe more than ever
that fancy cables is the-salt-of-the-earth. Come to think of
it you can do sensible things with your cables. Bi-amping, for
example. Some speakers also have several pairs of binding posts
for the drivers. Try to connect each separately to the amp. That
improved the sound in a couple of Mission speakers I had. I think!
Back!
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