Supratek Tubes and Tube Swappin' for Everybody

Hello,

First off, let's make sure we are only talking about the Syrah here.

You cannot use the 300B, PX4 or 45 tube replacing the 6SN7 tubes or any other tubes in the preamp without any modifications. The most obvious reason is that 300B and 45 have a different pin configuration, and number of pins, thus, different sockets required. The DHT (directly heated tubes) 300B, PX4 and 45 requires 4 pin sockets usually called UX4 sockets while the 6SN7 requires an octal socket (8 pins).

Let's leave the circuit characteristics of the Syrah for now.

regards,

Abe

Thanks for the clarification about which tubes may be used with the Syrah/Chenin. That's very helpful! I'm a tube novice :)

Powers - price isn't so much of a concern. I can spend as much as might be suggested if it will result in a corresponding increase in sonic results. I guess I'd put a cap on price only to the extent that the tube prices recommended are so expensive for my little Syrah but the resulting improvement is so small due to limitations of the Syrah that one could barely hear it than it might not be worth it. In that case maybe it would be worth looking at jumping up from the Syrah/Chenin to a higher end model preamp like a Grange or Cortese instead that can really take advantage of a better selection of tubes. Does that make sense? I guess it comes down to bang for the buck and living within the limitations of what can be reasonably expected out of a Syrah.

I was attracted to this preamp because of the extreme value it offers - best bang for the buck out there according to many and I haven't been disappointed in the least with its performance. But I lack knowledge in the whole world of tube selection so I'm a bit over my head in this department. If you have any suggestions that would really improve the sound of the Syrah I'll give it a shot. but if you think I may already be near it's limits and probably shouldn't toss too much into more expensive tubes for this model because it would be a better bang for the buck to upgrade the whole preamp I would take a look at that too. But honestly I'm pretty happy with what it has brought to my system so far. It is a huge improvement to the SS preamp I had before without any doubt. Right now its paired with a Pass Labs 250.5 and some older Watt Puppies. The tubes I have currently are the following from tube depot:

Regulators: Sovtek KT66 $49.95/pair
Line Stage: EH 6SN7 $11.95/pair
Rectifier: Bendix 6106 $39.95 ea

Thanks in advance for your help!

Hi there,
I got a Chenin just before Mick shut up shop and love it dearly.

If you can grab a pair of Kenrad VT231 black tube to replace the stock EH 6SN7. You are likely to get more body to the music and better bass. I've tried some Sylvania Brown base 6SN7, new russian made Tungsol 6SN7GT and RCA grey glass but still prefers the Ken Rad.

For the rectifier, i'm using the same Bendix 6106 and Russian Tungsol KT66 for the regulators.

I play vinyl quite a lot and thinks the Chenin phonostage is a star for a build in stage. But I did swap out the stock EH6922 with some NOS Russian Military 6H23N-EB from
http://www.thecableco.com/product.php?id=3887

Good tubes for not too much money but i couldn't help myself with a pair of NOS Siemens 6922 later on which were dearer but they paled against these Russian Millitary tubes, less sound stage depth, size and resolution. So not all expensive tubes are inherently better.

Incidentally, i've tried 2 solid state phono stages (still got the PS Audio GCPH) against the Chenin over the last year but i still prefer the Chenin by a large margin despite slightly higher noise floor.

Thanks for the clarification about which tubes may be used with the Syrah/Chenin. That's very helpful! I'm a tube novice :)

Powers - price isn't so much of a concern. I can spend as much as might be suggested if it will result in a corresponding increase in sonic results. I guess I'd put a cap on price only to the extent that the tube prices recommended are so expensive for my little Syrah but the resulting improvement is so small due to limitations of the Syrah that one could barely hear it than it might not be worth it. In that case maybe it would be worth looking at jumping up from the Syrah/Chenin to a higher end model preamp like a Grange or Cortese instead that can really take advantage of a better selection of tubes. Does that make sense? I guess it comes down to bang for the buck and living within the limitations of what can be reasonably expected out of a Syrah.

I was attracted to this preamp because of the extreme value it offers - best bang for the buck out there according to many and I haven't been disappointed in the least with its performance. But I lack knowledge in the whole world of tube selection so I'm a bit over my head in this department. If you have any suggestions that would really improve the sound of the Syrah I'll give it a shot. but if you think I may already be near it's limits and probably shouldn't toss too much into more expensive tubes for this model because it would be a better bang for the buck to upgrade the whole preamp I would take a look at that too. But honestly I'm pretty happy with what it has brought to my system so far. It is a huge improvement to the SS preamp I had before without any doubt. Right now its paired with a Pass Labs 250.5 and some older Watt Puppies. The tubes I have currently are the following from tube depot:

Regulators: Sovtek KT66 $49.95/pair
Line Stage: EH 6SN7 $11.95/pair
Rectifier: Bendix 6106 $39.95 ea

Thanks in advance for your help!

Just reviving this old thread as I have found what for me is the best regulator tube I have heard in my Supratek Chenin, that being the Valve Art 350B. I know there have been posts from others extolling the virtues of the WE 350B but that is SUPER Pricey! The Valve Art is $34.50 per matched pair from AES, and works great!

The sound is very open and spacious, with excellent bass (comparable to or even a bit better than the Sovtek KT66 I had been using) and an enormous soundstage. The difference was not subtle versus the Sovtek KT-66. So in my experimentation so far, I've found:

VA 350B > Sovtek KT-66 > NOS Tungsol 5881 > Sovtek 5881

Before I did the swap I did some reading about shunt regulators and found some articles stating that the higher the transconductance, the better the tube is as a shunt regulator. Although I could find no specs specifically for the Valve Art 350B, the WE version lists a transconductance of 8300 mho, versus 6300 for a KT-66, 5300 for a 5881, and 4700 for a 6l6GC. Based on that difference I gave it a try.

I did contact Mick to be sure the higher filament draw wasn't a problem and he said it was fine, so I don't think that's a worry - so far ~20 hours and no issues. I fine tuned the B+ voltage to remain at 300V after switching tubes (it was very close anyway) so the differences are not due to a change in operating point of the other tubes.

Just thought I'd share.