Supratek Preamp. and 6SN7's impressions

I have had a Chardonnay for over a year now and have enjoyed it immensely. I used to drive a Plinius P8 amplifier with it, which was an overkill (200 w/c) for my Reference 3a MM Decapo's. It was a fairly musical combination, though.

Recently I sold the Plinius and bought a First Watt F4 stereo amplifier. It is a class A, 25 w/c buffer type amplifier,(designed and built by Nelson Pass)which means it does not amplify voltage, it is a current amp. You need to have a high gain preamp to drive it, and the Supratek is perfect in that respect.

This also means that the characteristics of the preamplifier are passed thru the amplifier without any gain or editing -or at least minimal editing-. So, I thought this would be a perfect combination to study the effects of the 6SN7 tubes in the Chardonnay.

I have used the following tubes: EH, NOS Tungsols, RCA's, Sylvania's. Verdict: The EH came on top. More natural sounding in both tone, pace and in soundstaging. More vocal and instrumental body. The others seem to have more energy in the highs -brighter- and do not throw a soundstage as natural and effortless as the EH's do.

Also the same conclusion was obtained with the 6106 rectifier that some raved about in this forum.. It does not really function as well as a GZ34 or GZ37. It gives the impression of more dynamics but at the end makes the preamp sound more "hifi". Soundstage is also constrained compared to the GZ34's. Not recommended if you want your Supratek to work as intended. Mick had informed in an email that the 6106 does strange things to the circuit's operating voltages.

So, what would this seem to indicate, in my opinion, is that Mick apparently voiced his preamps. around this tube (EH and GZ34, etc.)to make it as musical as he intended. That works very well.

Sources: Shigaraki CD transport and DA with 47 Labs Dumpty power supply. Supratek Chardonnay preamp. Interconnects and speaker cables: Jena Labs. Power Conditioning and power cables: Jena Labs