Preamp Deal of the Century

Hello all. My Syrah will arrive in a week or two (ordered 6 months age, I don't mind the wait). First tubed component for me, very excited. Also I'm currently listening to two channel music (what I prefer) through an HT processor so the change should be phenomenal. Now comes the education into tubes. I found a place where I can buy KenRads at $125/pair and Sylvania 6SN7 metal base for $250/pair. Are these prices in the ballpark? I have no idea. This is more $ than I expected to be paying for NOS tubes. I assume NOS tubes are not in production anymore; what do when they are all gone? :)

My major confusion at this point is what about the rating letters after the 6SN7. Like GT, GTA, GTB, or WGT. How do I know which I should use? Do tubes like Tung-Sol VT-231 or RCA VT-231 also come with these letters on them? BTW, all these designations I’m using in this post I’m getting from a website as I write this; they mean nothing to me at this point, its like a new language I’m learning. When my pre arrives, will the stock tubes have one of those designations, and all I need do is make sure that’s on the NOS tubes I buy? I read on a tube seller’s site that these designations refer to a tube’s voltage and plate dissipation ratings, and to ensure good tube reliability you should probably run a tube at 70% or less of its maximum plate dissipation. Wow, this tube rolling is technical! :)

So anyone willing to help me out, maybe suggest the complete tube designation I would buy in a Tung-Sol Round Plate (VT-231 or 6NS7), RCA VT-231 black plate, Sylvania 6SN7 black plate, and Sylvania VT-231 black plate. In other words, do I need to buy a Sylvania 6SN7W black plate, not a 6SN7WGT black plate?

Also, anyone willing to share where they buy NOS tubes? Maybe those are well-guarded secrets since good prices on NOS tubes are hard to find?

Jeff,

here are a couple places for tubes:

http://www.upscaleaudio.com
http://www.thetubestore.com
http://www.vacuumtubes.com

I'm sure there are many more - Kevin at upscale audio is very helpful, I've also bought tubes from thetubestore.

Would like to hear about your preamp!

Most tubephiles will agree that the 6SN7GT and VT-231 sound much better than everything else. At least initially I would just pick up a pair of Ken Rad VT-231 black-glass and a pair of Sylvania VT-231. The Sylvania VT-231 usually goes for about $40-50/pr used in good condition and $70-80 NOS on eBay. Ken Rad VT-231's usually go for about an additional $20/pr on top of the Sylvania prices. There are very few actual NOS tubes sold on eBay regardless of the claims. However I wouldn't let that stop you. You can a get a couple of used pairs cheaply on eBay and once you determine your preference you can buy the bigbuck NOS tubes from a more reputable tube dealer.

I have a Cortese so the Syrah maybe different. Anyhow, Mick told me that in the Cortese the rectifier is set to output 370 volts. The voltage-regulator tubes burn 70 volts and the 6SN7's use the other 300 volts. Keep in mind that the 6SN7 is dual-triode rated at up to 300 volts/triode, so 600 volts/tube. 6L6G's and 5881's can handle 250-300 volts with ease. Mick runs the tubes very conservatively.

As far as power tubes. I think the ST shaped 6L6G's (Sylvania, RCA, Ken Rad, Tung-Sol, etc) are better than the Tung-Sol 5881'S and they are certainly less expensive. With rectifier tubes, I prefer the GZ33 over the GZ34. The GZ33 is less expensive, probably lasts longer, outputs more current, and sags less than the GZ34. I have noticed a slight voltage sag from my Cortese with the GZ34. It only occurs on complex musical passages while I am playing very loudly.

If you have questions about what tubes will work in the Syrah as far as tube substitution goes, I would email Mick "the Man" Maloney. He'll be glad to answer your questions and I am sure his answers are more accurate than mine.

Thanks Tonnesen and Jazzdude. So one path would be to find some used tubes first to discover what I like, then buy new for greater cost. Does it look like the site I quoted prices from (www.tubeseller.com) is reasonable?

Any suggestions out there for a resource (website or book or maybe in your own words if it can be put into one paragraph)that would get me up to speed on "rectifer tubes", "power tubes", and any other types of tubes in the Syrah, and that would give me an understanding of Jazzdudes sentence "...rectifier is set to output 370 volts. The voltage-regulator tubes burn 70 volts etc." This stuff sounds interesting.

When you say most agree that the 6SN7GT and VT-231 sound much better than everything else, do both Sylvania and KenRad make a 6SN7GT and a VT-231?

I just finished sending Mick a message with some tube questions before reading your posts. He has been very willing to answer questions along the way, looking forward to what he has to say on these questions.

6SN7GT and VT-231 from the same time period are the same tube. VT-231 is the military designation. You see it alot because from time-to-time the military auctions stuff in storage. If you are buying NOS/NIB 40's vintage 6SN7's it is probably easier to find VT-231's than it is to find 6SN7GT's.

IMO Brent Jesse has the most reasonable tube prices (with very good quality) of any online dealer. I have bought from Brent before and will do so again.

Bruce Wenger of BWS Consulting (search google) is probably the most service oriented dealer I know. He designs and mods tube gear and dacs but he also sells from his tube stash. Bruce always calls me a couple days after an order to make sure that I am pleased (no one else has ever done that) and if I bought two sets of tubes from him and found that I preferred one over the other he would let me trade in the less preferred set for something else (I've never taken him up on it though). If you buy something from Bruce you can be sure it is good. I told him once I wanted 4 pairs of NOS Sylvania VT-231 and he called me back later and said that he only had 3 NOS matched pairs that he could make and that any other matched pairs he had would be in used condition. Some other dealers would have been tempted to "MAKE" a pair just to get that extra sale, but not Bruce. Bruce's prices are not cheap, they are roughly on par with Bob Malecki of tubeseller.com.

I've bought from Bob before also and will do so again but he never has Sylvania VT-231's. Also Bob Malecki only has 6SN7's for sale, so no matter how much you like him you will have to go somewhere else for you power tubes and rectifiers.