Heretical Theory:
TDS Audiophile and the Quantum Symphony AC Conditioner
Marshall Nack
30 August 1999

Audio Puristís Philosophy: Straight Wire with Gain...

I have always been attracted to simple, elegant theories. If I'm not mistaken, this is what we're all taught in school. It becomes second nature at some point, and later on, it may become part of what we call common sense.

revphototds1.gif (14757 bytes)In the audio realm, the purist partisans believe that the fewer the links in the signal path, the less chance there will be of screwing it up. Less is better. The High End has bought into this to such a degree that we no longer have tone controls, we use the shortest signal-paths, and so forth. Some manufacturers advertise minimal gain stages and the elimination of negative feedback. Obviously, many High End consumers view these as good things.

Being partisan to this viewpoint I bought a passive preamp years ago. I did indeed find it more to my taste than any of the active preamps I've tried. There was less "editorializing". I agreed that less sounded better.

I suppose in a perfect world, theory should reliably predict what happens in reality. Entertain the following for a moment:

  • What is the condition of the AC as it comes out of the household outlet?

  • Are interconnects and speaker wire perfect transmission mediums?

  • Do components pass the signal untouched, only amplified?

  • Is any room free of frequency and acoustic anomalies?

If you've been around audio awhile, you know the answers to these questions are more or less "no". So how does this impact audio-purist theory? It can still be argued that given less-than-perfect components, adding anything more will increase the likelihood of further deterioration. On the other hand, if the "anything more" directly addresses the shortcomings in some piece of gear, then you're obviously better off with "more."

In responding to the above, I need to take a short detour to my editor's system. In my opinion it sets the benchmark of what is possible in a home system. Many's the time I've come away from listening sessions at Perry's, thinking the envelope has been nudged yet again. His system is CD-based, but doesn't sound like any digital I've ever heard. In audio, most virtues are usually on opposite sides of a continuum. If a system excels at detail it is often lean and lacking in body. Terrific sound stage width usually means compromised imaging. Perry's system has somehow managed to acquire lots of these opposing virtues. It has a satisfying deep bass foundation, yet the most delicate treble. It's warm and full-bodied and yet detailed to the Nth degree. Most of all, it's a relaxed sound. I've experienced listener fatigue only when he cranks the volume to show off dynamics.

Yet, I've always been ill at ease thinking about all the add-ons in his signal-path. I was hearing state-of-the-art sound, but I couldn't accept it coming from all those add-ons. I secretly thought: "Does he really need the Shakti Stones, the Z-System equalizer/pre-amp, the TDS, the Quantum Symphony AC conditioner, or the Argent Room Lens?" "Wouldn't it sound just as good, possibly better, with a simpler food chain?"

The Conversion of the Purist

Part 1: The TRUE DIMENSIONAL SOUND Passive Audiophile Enhancer

Two months ago Perry lent me a TDS audiophile black box. As stated, I was skeptical that any additional device in the signal path would be beneficial. So I was unprepared for the performance gain it gave me. The TDS is a small black box that goes between your preamp and amp. It does not plug into the wall. Installation only requires an extra length of interconnect.

Suddenly sounds had more weight, images were in sharper focus and had more depth. I don't mean instrumental image became more layered or more palpable. Palpability usually implies some degree of edge effect. The images were more clearly defined, but didn't have sharp edges. What they gained with the TDS was front-to-back depth, so that each image now occupied a volume of space. This volume held different kinds of information. In place of a flute-like noise, there was the telltale sound of air moving inside the flute, of different keys being depressed. In real life you can hear the musician blowing into the mouthpiece of the flute and the air moving inside the instrument. When an instrument gets louder more happens than just the dB level going up. The quality, or color of the sound, changes when it is played soft or loud. This makes the performance more interesting. All of this information coming across means your brain doesn't work as hard filling in the missing parts in order to make the perceived sounds make sense. It means you can relax.

On an average recording like George Szell and the Cleveland Orchestra doing the Mozart Symphony No.35 (EPIC BC1106) -- average in terms of sound quality; excellent in terms of performance--suddenly the individual sections of the orchestra were put into a musical context. Each section's part was audible as if you had the score open. And you could hear what it was contributing to the performance. You sit back and take it all in, or you can just focus on the cellos. Now you can appreciate the greatness of the composition from more perspectives.

How the TDS does all this is a mystery to me. What the manufacturer says about their patented technology is that it restores the harmonic spectrum to audio signals by "introducing a non-linear amplitude distortion of select frequencies." It is clearly an additive process. But on the evidence of what I'm hearing, this is Strike-1 against the purist theory. It is correcting some weakness that our components don't address.

Overall impression

With the TDS the timbre is darker, bass is emphasized but still tight, while the treble was scrubbed of electronic glare. The stage is much wider and deeper. Instruments are more complex and full. All this without any increase in grain. I found the TDS Audiophile Enhancer a solid improvement. At its price ($395), it's a no-brainer recommendation.

Part 2: QUANTUM SYMPHONY AC Conditioner

At Perry's suggestion I contacted Bill Stierhout of Quantum Products, Inc., and requested one of his Quantum Symphony AC conditioners for review. Bill sent me two units since listener feedback indicated that bigger systems require more units.

Bill claims they redress the chaotic nature of the electrons in your AC line and put them into alignment. Once the electrons are aligned, they tend to stay that way. When your components see this coherent electron flow, they don't need to work as hard. Less strain on the components means they work cleaner, similar to an amp running in class-A mode. It is believed that class-A watts sound better.

In the case of the Quantums, the claimed improvements are in dynamics, transients are quicker with more harmonic content, treble harshness is eliminated and front-to-back imaging is improved. Oh, and Bill says you should see a reduction in your electric bill. If components are working more efficiently they don't consume as much electricity.

I left my system as it was and added the Quantums. These units are plugged into available outlets in the vicinity of your components, the closer the better. They work in parallel to your existing AC conditioner. Nothing plugs into them. No break-in is required.

The changes are obvious and immediate. With the Quantum Symphony in place, the room acquired a more intimate atmosphere. There was greater ease to the presentation. Could it be that efficiently working electronics do have an impact on the perceived stress level?

I was shocked when I played LPs that had always distorted on crescendos. They now played distortion-free. It makes you stop and rethink your assumptions. I always assumed the distortion was in the grooves, certainly not in my $2,500 cartridge. I hoped not in my amp. Now suddenly my amp is performing like a champ. The whole system exhibits less strain. This level of improvement may happen when you upgrade a major component, usually for big bucks. And, even then, what you get is a reduction in this distortion. Now it seems almost gone.

Initially I missed the treble explosions I was used to hearing in Dizzy's riffs on The Alternate Blues (Analogue Productions APR3010). These were dynamic peaks I've enjoyed that took his trumpet out of my room, out of the recording studio, to some unnatural place conjured up by the interaction of my components.

In place of this "WOW" hi-fi effect was a more realistic dynamic peak which revealed the articulation of each note. I could now discern the movement of air in and around the trumpet, and hence the human effort it took to produce the notes.

The effect is similar to the TDS and synergistic with it. With this combination, the action of the instruments becomes audible in a shocking way. The treble glare which I had grown accustomed to was further reduced.

Macro-dynamics have a wider range and go louder more naturally. When Bill visited and heard Dizzy, he was blown away like the guy in the Maxell tape poster. Don't get me wrong, it is still a long way from natural dynamic range. But this is amazing, especially considering I'm using a passive preamp.


I found Bill's claimed areas of improvement to be on target. The Quantum Symphony is doing something audibly corrective to the AC power. This was Strike-2 for the purist theory. At a cost of $300 per unit, the Quantum is a bargain. We'll see about the monthly electric bill.

Similarly, I suspect the TDS is correcting something in the audio signal, as the manufacturer claimed. These are two add-ons that bring cutting-edge technology to the audio enthusiast at a real world cost. The combined effect is more beneficial than any single component upgrade I've experienced.

The audio purist theory reads well on paper and remains a virtuous goal. In the meantime, there have been positive developments in scientific theory and engineering reality that bring us valuable products. Itís possible that next generation wires will incorporate TDS, or Quantum, or Bybee technology. Then the purist will be happy again, since the boxes will be built-in.

P.S. Strike-3 was experiencing the BYBEE Technologies filters. These black boxes are inserted at the tail end of your interconnects and speaker wires. They apply recent quantum developments to audio signals.

--Marshall Nack

Reference system: Linn LP12 with AQ7000 cartridge is output to a Graham IC 30 cable, which in turn is input to a BYBEE interconnect filter. The BYBEE goes into Dan Fanny's Non-Signature phono stage. Output from the phono stage to a McCormack TLC1 passive line stage is via BD meter of Harmonic Technology Pro-Silway MKII wire. The passive line stage feeds another BD meter of HT Pro-Silway MKII, into another set of BYBEE's, then into my BAT VK200 stereo amp. Magnepan MG 3.3 speakers are connected via a 6' HT Pro 11 Plus, also having BYBEE speaker filters in line.























































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