Review: Tube Audio Design TAD-1000 Tube amp

Category: Amplifiers

I bought a pair of Paul Grzybek's TAD-1000 Monoblocks about five months ago. Since then I've had a few queries on how I liked them so I thought I would post my own notes on setting them up along with a brief review. Hopefully, my system and experiences are enough different from others that this is worthwhile.

Setup

Follow Paul's directions. You definitely want to take your time in setting the bias and feedback and selecting your 'normal' listening mode - Triode (3) or Pentode (4). You have to do the bias first, of course (350-370 on all four on each amp after a 10-minute minumum idle warm-up). After that I would recommend that you set the feedback to mid-range of the knob travel. Pick your normal mode (Triode or Pentode) by switching the mode while you are listening to some well-known music. Then set the feedback on both monoblocks while listening to some familiar music.

I find I like the detail and clarity of the Triode wiring but others prefer the punch and boost of the Pentode mode. There are certain recordings that sound better with Pentode - some of the older Beatles stuff comes to mind. But, I usually leave the monoblocks set to Triode and just turn them up a bit, even when listening to something like Led Zepplin, instead of switching to Pentode - but you definitely get more power in Pentode. The feedback setting makes a LOT of difference in how the harmonics affect the sound reproduction. It's a trade-off. Adjust them until things sound true-to-life to your ear. You will want to do this with different types of music and music passages. It is probably best to use vocal, piano, and other mid-range passages to fine-tune the feedback settings. You will likely find that the perfect setting for one passage is not the same as the perfect setting for another recording or passage. It will also probably depend on the source. What's nice about the 1000's is that Paul gives you control of this trade-off instead of using a built-in setting.

For the gain controls on the back of the monoblocks, I would set them to just a bit off of full open - crank them all the way up and then back off about an 1/8th of a turn. I make this recommendation not out any specific technical basis, but just on my own belief that it is not a good idea to have any control set all the way to the stops as a permanent state of affairs. I use the gain controls in my own set up as a method of balancing the sound stage in my particular listening area.

Results

Once you've set up, you can start listening with a fair degree of musical pleasure. Break-in was noticeable but fairly short-lived. I would say not more than a few hours. During that time I did notice a few overly bright spots and some passages that sounded a bit 'jangly,' if that makes any sense to you. But nothing was persistently noticeable. After that short period, things have been very, very good in the listening department.

Bass is immediate and full. I have a home theater system with a subwoofer and a solid-state AV amp (Harmon-Kardon AVR520, Polk Audio RM-7 5.1 speaker system). I output from the Denon source to both the home theater system via a fibre-optic digital audio cable and to the stereo system via right-left RCA cables. For those of you not familiar with the Soliloquy 5.3 speakers, see specs below - they are not big thumpers. The bass through these speakers with the stereo setup rivals the bass of the home theater system - even at the vibrate-the-walls, impact-tremor level that is more felt than heard. This was so surprising to me that I toyed with the idea of getting rid of the home theater system and just using the stereo system for all sound reproduction. But, the home theater does offer the center speaker that makes dialog come through with such clarity - that and the surrond-sound effects make it worth keeping.

For the mid-range, vocals and piano, etc., the sound is right there. You can listen to Norah Jones, for example, close your eyes and imagine that you are sitting at a table right in front of the stage. Highs come through pure and bright and clear, without being obnoxious. The sound stage is broad and pervasive. I can sit at my desk across the room and to the side of the system's normal listening area and still enjoy music with very little reduction in the presence of the sound stage.

After having these TAD-1000's for a few months now, I can say I am more than happy with them. There are always improvements that can be made, but the addition of these monoblocks has given me my holy grail of sound. Well, at least for the time being. ;-)

Associated gear
Tube-Audio Design TAD-150 tube preamp with signature mods by Paul Grzybek

Soliloquy 5.3 Speakers - Each speaker has two 5 1/4" drivers and one 1 1/8" tweeter and is floor-standing with spikes.

Analog Source - Music Hall MMF-9

Digital Source - Denon 3910 with mods by Mike Powell (HRAM)

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