Greg Weaver

December 1997

More Fun and Games with the....
True Dimensional Sound TDS-II Analog Audio Processor

I had barely finished Mike Masztal’s review of the True Dimensional Sound TDS-II Analog Audio Processor when I fired off an email to him. Did he still have it? Yup! If so, for how long? Indefinitely! Could I borrow it? Yup, again! Being the thoughtful, considerate SoundStager! that he is, he shipped it off to me right away! I had it in less than a week!

[TDS-II]I had planned to put the device through several stages of testing, starting with a basic no nonsense system right on up through my reference gear. So, the minute it arrived at my workplace, I threw it into the fray. The first system I tried it with consisted of a Jolida JD601A vacuum tube output CD Player feeding a Rotel RC970BX pre-amplifier. The output from the pre-amp, rather than feeding an amplifier, was fed directly to the new Paradigm Active/20 loudspeakers via MIT Terminator 6 interconnects. The whole system retails for under $2500.

My first impression was a bit bewildering because of the rather drastic volume change when activating the TDS-II. After getting comfortable with matching the levels, I was VERY impressed with what was happening. On this system, new levels of depth and layering of the soundstage revealed themselves. Pianos and vocals, already done wonderfully by this little system, were enriched and even more engaging than without the unit. The most pleasant surprise was the apparent tighter focusing of images and enhanced clarity of instruments away from the center of the soundstage. It was as if they were all being "seen" through a "sharper" lens.

Next was my office system at home, the one I listen to while writing. I am currently using an old Denon DRA 350 receiver, a Luxman D105u CD player, a B&O Beogram 2402 table with the MMC20CL cartridge, Optimus LX 4 loudspeakers (with my home built x-overs) and on old 10" sub box driven by a McIntosh MC50 mono amp. I’m using my home brew inter-connects and speaker wire. The whole thing comes in at about $3200. Granted, the speaker positioning is bad, with one speaker on each side of my monitor, about three feet apart, and only 10 inches from the back wall. What a transformation! Pianos lost all those "plinky" overtones that I dread, voices came to life and the soundstage and image - my God! WOW!

Now you can imagine how I about tripped over myself inserting this into my reference system. The system currently consists of; a Linn LP12 with a Magnepan arm and Monster Cable cart; a Pioneer Elite Stable Platter Transport; an Audio Alchemy DDE v3.0 DAC; a Threshold FET nine/e pre-amp; the Clayton Audio S-40 amp; Gallo Nucleus Solo’s; my home brew subwoofer (dual 12" woofers in a push-pull compound isobaric load) driven by a modded Hafler MOSFET SE240 running in mono and fed by my home brew x-over at 42 Hz. All components were connected with my home brew solid silver signal tape and loudspeakers were coupled with the MIT Terminator 2 bi-wires. Switching the unit into the system revealed that variation in loudness yet again. The whole spectrum of sound tended to tilt towards a brighter overall character. Measurement showed it to be almost exactly 3dB of increase. That worked out nicely since the detented volume control on my Threshold changes in 1.5 dB steps. All I had to do was move the volume knob 2 steps up or down in order to match the volume of the engaged or disengaged output level. Okay, now we’re ready to go. On it went for critical listening and ... hummmmm. What was going on here?

In went Roger Waters Amused To Death. Firstly, the stage did deepen somewhat and the mids did get just a bit more lush, as it had done with my previous two experiments. Instruments to the sides of the stage were again presented with more focus and specificity. And although the Q Sound special effects tightened up in their extreme positions, the bass had become bloated and fat. The whole rhythm seemed changed, and not for the better. It was as if the lowest registers were slowed down and thickened.

Moving to the 1977 disc CSN by Crosby, Stills & Nash continued to chip at the unraveling of the performance of this device, in this particular system. Indeed, the vocals were more natural as well as better focused and delineated. There was that superb layering of the soundstage front to back too. But there was a slurring of the rhythmic nature of the music. There was a bit of compression to the vertical height of the stage and, more alarmingly, a bit of added whiteness to cymbals and the higher frequencies in general.

These attributes reared their head with disc after disc and record after record. As well, the noise floor was elevated somewhat, taking away some of the subtle detail and "blackness" from lower level and silent passages. Checking the case of the unit with my VOM referenced to ground revealed 3.4 VAC floating on the unit. Reversing the polarity of the "wall wart" power transformer revealed a modestly lower 2.9 VAC floating potential. While this seemed to help slightly, it did not correct the low level "hash" imparted to the system overall. This is a shame because the rest of what the device was doing was very much to my liking. Boy, does this whet my anticipation of the passive version due next year!

This little black box offers near magical transformation of any but the most exotic system in which it was auditioned. Don’t take this as damnation, folks! Far from it. This little gizmo offers a ton of music for its modest $295 ante. It offers more natural timbre, much better focus and imaging, more clarity to instruments (especially those not at center stage) and a warmth and liveliness akin to a live performance. GO FIND THIS UNIT AND LISTEN TO IT! You will not believe the transformation it can affect! If you are not using a kilo-buck system I can, no make that MUST, whole-heartedly recommend this device. Even if you are using the latest and greatest, you owe it to yourself to audition the TDS-II. You may not even mind the few little things that I am knit-picking.

...Greg Weaver

TDS-II Analog Audio Processor
Price: $295 USD

True Dimensional Sound, Inc.
1450 Madruga Avenue, Suite 404
Coral Gables, FL 33146
Phone: 305-668-9198
Fax: 305-668-9334