Preamp Deal of the Century

2 months ago I sent my Syrah back to Mick for an upgrade to Chenin. It is no doubt that there is a hugh improvement on the phono stage but the choice of rectifier is sacrificed. I can no longer using Bendix 6106 or even Mullard GZ32 (background noise was heard). Mick explained that both tubes are not running at the proper operating points. For the Bendix, it has greater voltage drop than the 5AR4, puts out 350V against the 5AR4's 370V. The lower voltage doesn't let the regulator work properly. In other words, the regulator is "starved" with the Bendix. Same situation applies on the GZ32 but the noise is not as serious as the Bendix. The phono stage on Chenin is obiviously more demanding and sensitive than Syrah. Any comment?

Ecmlee, the Mullard GZ34 or the Philips Miniwatt GZ34 metal base are better rectifiers then the Bendix or the Mullard GZ32 in my opinion, so rectifiers in your upgraded Syrah shouldn´t be a problem.
BTW I didn´t know that´s possible to upgrade the Syrah to the Chenin status. What´s the cost for it? and, is the final result a "real" Chenin?.

Jazzdude, Amandarae: Thanks very much for the suggestion. Mick gave me some instruction, I found the cause and fixed it: A part got loose and bare wires touched the ground causing short. I glued the part to the frame and the music came up as expected. I will wait patiently for the break in as I learnt from Amandarae. Thanks again for sharing your knowledge. You guys are awesome!

Ecmlee,

I do not know about the Chenin's phono stage being sensitive compared to the Syrah since I have no experience owning the latter. All I know is that I get better feedback replacing the 6C4 tubes than the 6922's in my phono stage. At present, I am using the Sylvania Gold Brand gold pin 6C4 and very happy with the results. A few post above, I tried several other 6C4's and I can say that I am finding the result consistent with what I posted before.

Finally got to put the Cabernet in my system tonight. These are my initial impressions. My Cabernet uses the WE 101D. The WE 101D has a UV-4 base that requires different sockets than the TJ 101D (UX-4 base) and the sockets are not easy to come by. For initial listening I took the same tubes I had in my Sauvignon and dropped them into the Cabernet with the addition of the WE 101D. My Sauvignon is the older version without the 12b4a only has about 12db of gain.

Initially when I recieved the Cabernet from Mick the RCA inputs and outputs would not work with my interconnects which have WBT TopLine RCA connectors. To get any sound at all from either channel I had to hold the interconnects in the jacks just so and if I released the IC's the system went quiet. Mick replaced the RCA inputs/outputs and the problem was corrected. I had no such problem with my Sauvignon which uses different RCA jacks.

The Cabernet improves upon the Sauvignon in several areas. The Cabernet seems faster and more intimate. It has even greater heft and slam in the bass department. The tonality is purer across the band and the transparency is improved in the midrange. Otherwise the Cabernet has the same general SupraTek 'signature' sound as the other pramps in the lineup.

When I initially turned on the Cabernet I noticed the slightest hum in my system from the preamp. The hum is extremely low level and not even noticeable from across the room. I mention it only because there is no noise at all with the Sauvignon.

To make an analogy in fine-tuning between the Cabernet and Sauvignon, I liken the Sauvignon to a road rally car and the Cabernet to a GTP endurance racer. This is probably because the Cabernet uses a DHT triode which are normally more sensitive to power supply. So in the Cabernet I think most will find that the selection of regulator and rectifier has even more impact on the sound.

Note that the DHT's tend to be more microphonic than most tubes. More so than say the Sylvania VT-231 and Ken Rad VT-231. In my own system my WE 101D are not noticeably microphonic so don't assume that all 101D will be microphonic.

So far, the Cabernet with the WE 101D is a definite improvement in my system and given my personal tastes. In my journey I have come to the opinion that thare is no such thing as "the finest...", "the best...", etc. Because as components and systems become more resolving, system synergy and personal preferences become an increasing factor. Surely though the Cabernet is worthy of the consideration of anyone exploring possibilities among the finer preamps in the world.