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all parts in audio chain are equal some are more equal then others speakers are the most equal of all

Lowthers on open baffle Why? Quite a few reasons. Mainly I am atracted to simplicity. Plus I am lazy too. Only the simplest can reveal the most complex. There is no simpler speaker arrangement than open baffle.  To me enclosure and crossover are unnecessary evil. No enclosure is best enclosure. As well as no crossover is best crossover. Do no evil, hear no evil! Lowthers have been used in almost any possible arrangement. Large closed enclosure, bassreflex enclosure, mostly backloaded horn enclosure, Voight pipe,  transmission line, front loaded horn and so on. I have been listening to Lowther on open baffle for more than ten years now. Finaly there were other people putting Lowthers on open baffle, thanks to Dick Olsher and Bert Doppenberg. Lowthers sound on open baffle very transparent, fast and alive. Very much like live music. Side cancelation sharpens the sound beam thus preventing reflections from the nearby walls. High directionality brings clarity. Reflections from the walls, those reaching listener within first ten miliseconds after direct signal, are almost eliminated by open baffle arrangement. Sound radiated towards back of the baffle is no problem, when it reaches listener it is already delayed by a significant tens of the miliseconds and diffused enough. Actualy, it is giving spaciousness to the music, a feeling of reverbation in the room without obscuring the original front signal. Once you will hear a good open baffle speakers, like those from Audio Artistry or Genesis, you will never go back.

I have noticed that live music sounds typicaly louder and more powerful than reproduced. Even piano alone can play pretty loud low frequencies. Not to mention church organ. Low frequency extension of speaker is very important and not an easy task to achieve.  Lowthers alone in any box will sound anemic, rolled off, coloured and so forth. Lowthers, frienkly, do not produce very low frequencies even in backloaded horn enclosures. Furthermore that bass is not deep for mouth opening is often patheticaly small, it is artificialy sounding due to phase shifts between front signal and rear signal, has uneven frequency response due to comb effect and so forth. By releaving Lowthers from low frequencies one decreases their distortion. Why not to use Lowthers for what they are best suited for, midrange and hights? Thats why I use Lowthers only as satelites from 150 Hz up.

My two subwoofers consist from two 15" woofers in inifinite baffle enclosure. These subwoofers moves lots of air at 25 Hz. Hughe magnets  have no problem to move large membranes + 5 mm. I wouldn't have heart to ask twinky Lowthers to do that, would you?... Dedicated subwoofer amplifier allows precisely to set its volume and cut off frequency. And one more thing. There is no such thing as slow or fast subwoofer. All subwoofers are inherently slow. Its the upper harmonics reproduced by midrange which makes bass sound fast or slow. Two subwoofers sound different for they have different frequency responses. If two subwoofers have the same frequency responses, horn loaded or not, they sound the same. If you appropriately cut off upper frequencies of "fast" subwoofer, it becomes "slow" subwoofer. It's the integration between woofer and midrange which determines how the bass will sound.

Well. I could't help not to start with speakers. I do consider them the most important part of reproduction system. But signal sources are very important too. If you compromise the sound in front end by choosing poor signal sources, there is very little you can do later.              When it comes to CD player, I settled with JungSon. I did not want to buy generic CD player, because together with LP's, CDs are my major signal source and sound of the CD player is important to me. On the other hand I do not want to spent megabugs on high-end players like those from Krell or Wadia. JungSon is definitely high end cdplayer without the high end price tag.

Pioneer RT-707

Pioneer TX-9500 MkII

Well, in order to hear the sound from speakers one has to take line level signal and put it through an amplifier.

This is my preamplifier and amplifier. They are based on  Steve Deckert's Zen Amp SE84-B. Gives roughly sweet 2 watts per chanel, plenty for Lowthers.  Very clean and musicaly sounding amp. I know that 20 watt SE output trafo for 2 watts amp is an overkill, but that's what I had that time. At least I can not saturate the iron. These Hammond SE output trafos sound excelent.  I would not use this amp to drive bass section or low efficiency speakers. I tried, the result was not pretty. Works great with Lowthers from 150 Hz up, though.

Well, in order to deal with open baffle cancelation I have 31 band 24-bit digital equalizer/RTA Behringer Ultra Curve Pro 8024. It works exactly as famous Accuphase, only costs ten times  less.  It measures and equalizes room response using external microphone placed in your listening position. The result is stunning. Dramatic change in music fidelity. It equals stepping into a concert hall. Everything is simply in the balance.  I feel I'd like to comment a little on this issue. Offcourse it measures steady state using pink noise rather than first arriving signal which might differ slightly due to standing waves making a whole issue a little bit more complicated, yet it does very good job in balancing frequency spectra. It is not however a replacement for accoustic room treatment.  Many people think that equalizers have no place in todays audio. I disagree. In order to hear reproduced piano as piano again a closest possible tonal balance is required. It means upper and lower harmonics must stay in the same ratio to the fundamental. Any disbalance is heard as colouration. Even your HiFi has the flattest response possible, your room is a different story. And often very neglected. To flatten the room response, equalizer is required. And to measure the room you need microphone, signal generator and SPL meter....or you buy Ultra Curve Pro 8024 from Behringer.

My audio system in summary:

Signal sources: tuner Pioneer TX-9500 MkII, cd player JungSon Moon Harbor MkII, reel to reel tape deck Pioneer RT-707  with dbx 228 type II tape noise suppresion system/dynamic expander, casette deck Onkyo Integra TA-2070, digital tape recorder Optimus DCT-2000, turntable No1. Technics SP-25 with cartridge Benz Micro ACE on tonearm SME 3009 amplified by Ortofon STM-72 step up trafo and diy phono preamp, turntable No2. Technics SP-25 with cartridge Audiotechnica AT-OC9 on tonearm TESLA PU1101 amplified by Ortofon T-10 step up trafo and Sparta studio phono preamplifier. Signal processing: diy signal selector selects the line level signal which goes through 31 band 24 bit digital graphic equalizer Ultra Curve Pro Behringer 8024 to flatten the room response with mic placed in listening position, output from equalizer is then attenuated with 24 position stepped attenuator to desired loudnes, attenuated signal is MOSFET buffered (Metaxas mosfet buffer) then passively split at 150 Hz (Dan Hildebrand crossover). Signal amplification: low pass output, 150 Hz down, is  amplified by stereo 2x100 watts AKAI chip amp and fed into two 15" woofers in infinite baffle enclosures, that takes care of the bass, high pass output, 150 Hz up, is amplified with modified Steve Deckert's Zen Amp SE84-B and finaly fed into pair of Lowthers DX3 on open baffle, that takes care of rest of the frequencies from 150 Hz up. Tune to your favourite station, spin your favourite CD or LP, sit back and relax.  And most importantly, enjoy the music! Yours, Ed

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