Supratek Owners Thread

@tksteingraber 

I have both a Chardonnay and a Cabernet in two different systems and use Blackburn Mullard 5AR4's in both mainly due to the slow start-up feature.  Have used all of the other compatible 5 volt variables but always end up back with the 5AR4's.  As I leave my SS amps on all the time I don't get the noise at start-up and especially turn off with the 5AR4's I get with the other variants.  My next favorite of the rectifiers are the RCA 5AS4's a 5U4 variant.  In both preamps I am using the 6L6 tubes Mick supplied as I tried other modern ones and didn't hear a difference.  Never had a reason to own NOS samples.  Am using RCA 6SN7 GT's currently in both units but in the past have had good luck with Hytron 6SN7 GT's and Raytheon VT-231's. I own several NOS pair but never saw or heard the fascination with 5692's. I own two pair of 1943 Sylvania GT's that I bought NIB almost 25 years ago that on occasion I will put in one pair in one of them just to see if they can stay put but it hasn't happened yet. After almost four years of rolling 6SN7's in the two preamps I'm kind of settled in for a while with what's in them. 

@jackd Great info exactly what I was looking for.  Much appreciated.

@tksteingraber I have put many tubes through my Cabernet. Keep in mind that sounds good will vary depending on what tubes I have in mt amp. When Mick built mine I had him put in a 6v/12v switch. Best thing I ever did. 12sn7 are much less expensive4. 

Favorite 6sn7(ish) tubes in no particular order:

Raytheon 6f8g T plates

Sylvania tall plate 14n7. They aren’t the same as the 7n7!

GEC/Osram/Marconi b36

Ken Rad round plate 6f8g

Interestingly, to me at least, is that I haven’t really liked having the Sylvania so called bad boys or Tungsol black glass, round plate in my Cabernet. And, yes, they are actual bad boys with the right dates, construction etc. I do like the Tungsol BGRP as drivers in my push pull amp. 

I have also had a lot of luck with single triodes with the use of adapters. Mick makes his Grange with 6j5. The 6/12j5 and equivalents, while rising in price quickly, are still good deals compared to the 6sn7 market. Here are some of my favorites:

Radiotron (from Australia) 6j5gt

Raytheon 12j5wgt

National Union JAN 12j5gt

Cossor branded 6c5g. There’s some debate who actually made these but they aren’t the GEC. Currently available from Langrex.

GEC l63gt brown base. 

Fun fact, the 6c5 is a good substitute for the 6j5 and I got Mick’s blessing to use them in the Cabernet. The 6c5 is actually, literally, a 6j7 triode wired so it is possible to use that configuration with the appropriate adapters as well. Haven’t done that yet but I will soon. 

@isaacc7 Thank you for your helpful tube expertise.  I am not familiar with many of these tube types.  Which types would be direct drop in’s for the 6v cabernet without using adapters?  Much appreciated!

Heh, just realized all of the ones I mentioned need adapters lol. These should be pretty close to the same tubes if you get the 6sn7 versions but the prices will make you cry:)

GEC/Marconi/Osram b63

Raytheon VT231

Sylvania 6sn7wgt 

I’m not sure if there is an equivalent 6sn7 to the round plate Ken Rad… My advice is don’t be afraid of adapters, especially if you want access to the best sounding tubes at a reasonable cost. 10-15 years ago you could buy any tube you wanted even if some were more expensive than others. Now some of the best tubes are difficult to find and are incredibly expensive when you do find them. I think the NOS tube rolling game has just about run its course, at least for the generally accepted “best” versions. You can still get great single triodes. A 6j5 is just a half of a 6sn7 so two of them are exactly the same electrically. Mick would be happy to make a preamp with 2x 6j5 instead of 6sn7 if you don’t want to use adapters. Or do what I did and get the option to use 12v tubes *and* use adapters:)