6SN7GT VT231 TUBES

I've always used Raytheon VT-231 tubes. Since I have my own computer tune tester I find samples on eBay for the most part. If I use a tube vendor my go to people are Andy Bouwman at Vintage Tube Services and Brent Jesse.

I bought a bunch at a rummage sale in the 90s, but I'm not parting with them!

Tung Sol did make VT231s

Brent Jesse great to do business with…..

Brent Jesse great to do business with…..

                                   +1

    I bought his last NOS Tung-Sol RP, 6SN7GT, matched pair.

               A perfect pair and: I love ’em!

I bought most of them through Ebay from 2018 to 2022.

Most of them were good.

I have all the tubes you mentioned including TS bgrp.

Now my favorite are 6f8g tubes which sounds fuller than vt231.

I may have the most comprehensive collection of 6sn7 or variants.

https://forum.audiogon.com/discussions/shootout-of-nos-6sn7-tubes

I have 50 different kinds and total more than 120 pairs.

But I do not sell my tubes. They are my lifetime collection.

Thomas

www.langrex.co.uk

I don’t use these tubes, but what’s the point of responding to a question with essentially, ‘those are great/amazing tubes, I have dozens of pairs that I’ll never use/sell/share, and good luck finding any because I’ve hoarded them all’…?? If the tubes are that good why not get them out there for others to enjoy? 

+1 for Raytheon VT-231’s! The Ken-Rad VT-231’s have the most solid bass of all the 6SN7’s I’ve heard in my Cary SLP05, Schiit Freya+, and Schiit Saga. The 5692 versions are smooth sounding. My favorite combos now are a quad of Raytheons in the Cary’s gain stage with by a set of CBS Hytron 5692’s in the XLR input buffer. With the Freya, black glass Ken Rads in the gain stage followed by the 5692’s in the buffer is my favorite combo, and I use a Sylvania 6SN7 GT JAN (“Bad Boy”) from the early 1950’s in the buffer. 
 

I have a quad of NIB red base GE 5692’s (RCA made) that I can’t wait to try as well, with several other JAN versions of RCA, Sylvania, etc.

For the money, the best I have heard are 1960’s NOS Sylvania 6SN7 GTB’s bought for about $35 apiece from Brent Jessee that have an exuberant, sparkly top. They sound significantly better than any of the new production tubes that I have experienced.

 I can’t recommend Brent Jessee enough, and will add that I have not yet experienced a bad experience buying NOS or used tubes from a variety of folks on Audiogon or US Audio Mart. I love the tonality of the 6SN7 tube, finding it to sound more natural and less hard than any 12AX7 tubes that I’ve live with for over 45 years (my favorites were Dutch Amperex, less dark than Telefunkens in my SP6B and Marantz 7C, as well as GE 5751’s used in the phono section of the Marantz).

I meant to say that I used the Sylvania Nad Boy in the buffer of my Saga.

Bad not Nad! 

I'm using the Sylvania 6sn7 gtb tubes right now and love them. I actually bought several sets just to have backup. I also have a few sets of the Raytheon and Tung Sol 6sn7gt (not the oval mica). I think they are really close but slightly prefer the Sylvania. The Sylvania 6sn7 GT 3 hole Bad boys are a little bass heavy in my system but have great soundstage and some spooky holographic detail that I do love. I could certainly live with them.  I also tried the Ken Rad VT-231 clear glass but I have not found a set that wasn't microphonic unfortunately.  I'd love to try the oval mica TS VT-231 but those prices have just gotten too steep for me. Running $ 800.00 a pair etc. Wow!

I have heard that the military VT-231 designation is overblown and many of the standard 6sn7 GT or GTB from the same era sound no different. YMMV

Thomas,

I've read through your 6sn7 tube shootout many times. It's a great guide and has helped a lot in my selection. Any particular 6f8g tubes that you prefer?

Thanks,

Mark

All of them are pretty great, and the final choice is going to be very system & listener dependent. More often than not, I like Tung-Sol black glass round plate 6SN7 the best - if I had to pick one, that's it. Unfortunately, I've had the bad luck of heaters going out on a few of these. 

I prefer Sylvania (side getter) VT231 over RCA. Sylvanias in general (through the 1950s) are pretty cool with me. Next are Hytrons and Ken-Rads. And RCA last (but still nice). I haven't had the pleasure of trying the Raytheon VT231, but they look lovely! Heck, even the Russian issues (Electro Harmonix, Tung-Sol) can be good - they measure VERY strong in transconductance, and can sometimes be best-in-slot for driving lots of big KT tubes. 

What I found is that vintage 6SN7GT tubes are best suited for the input stages of power amps. In these slots, you're getting all of their sweet sound with none of the downsides. In preamps, these old tubes are going to have all kinds of noise / microphony issues. Even worse in phono stages. As an output stage tube in headphone amps (this was more popular circa 2000s head-fi), they are very weak compared to many other better alternatives. 

For preamp slots, it's best to stick to later GTA / GTB issues (lower noise & microphony), or modern Russia/China tubes which can be selected for very low noise (and matched tightly, to boot). 

6SN7 is a GREAT tube, but it's important to respect its proper role and limitations. 

@vintageadict 

RCA, Sylvania, Tungsol 6f8g are good.

But Tungsol seems to be overpriced due to hype.

Raytheon sounds more shapr and clear thus dependent on system and taste.

Thomas

Interesting that I mainly use the 6SN7 tube family in my preamp and have not experienced any noise or microphony issues with older tubes.  Just a couple outright failures.
My preferred 6F8G tubes are Raytheon with flat ladder plates (very hard to find).  Step up from the T plate version.  National Union round plates and RCA Gray Glass are also excellent.

@shkong78      Are you still on the Melz 1578 bandwagon? I bought two pair from an ebay seller you had cited. My experience with them was dismal as none of them made 50 hours use. I just ditched the last pair a few days ago. Don't get me wrong...I'm not blaming you for my outcome, just wondering if you've had better luck with longevity.

I have 3 pairs of Melz but no more interest in them due to noise problem.

I also collected more than 8 ohter Russian tubes whish also sound decent.

I just put a 6F8G in my amp and I think I like it better.  Seems to have tightened up the bass.

RCA black glass.

Brent Jessee, great source of information, huge selection, good guy to deal with.....he doesn't give his stuff away, but he has the inventory

I know this is not really what you're asking but I have a VTA SP-14 and just replaced the 4 6sn7's with 7n7's (you'll need a base adapter, readily available on ebay). A much more open and detailed sound with no etching of the treble. The bass seems a tiny bit looser but still powerful and tuneful. Very impressed!

I also tired four different kind of 7n7 out of curiosity 2 years ago.

Although they sound clear and detailed but lack overall musicality compared with vt231 or 6f8g tunes.

Thus no more interest in 7n7.

Thomas

But 7n7 tubes are reasonably priced.

Thus you may try them for fun or different flavor.

You never know until you try them in your system.

Thomas

One of the best things about the 6sn7 tubes other than they sound great is there are still a ton available and many at reasonable prices. I use them in a Modwright LS 100 preamp. I didn't go all in on the Tung Sol round plates that go for such high prices but I have a nice selection of Sylvania, Raytheon, Tung Sol, and RCA that should take care of me for many years. I much prefer those to any newly made tubes I have from Russia or China. The somewhat standard Sylvania 6sn7 gtb sound very good in my system and they are plentiful. 

I love the Tung-sol 6NS7 I use them in my Triangle Arts I've owned the older version & his newer line. Pre Amp & Mono-Blocks. They're inexpensive balanced & sound great. When I compare the difference in prices I'll go with Tung-Sol's. More money for vinyl.....

I have a pair of Sylvania VT 231. 6SN7GT on my OPPO 105 Modwright and when I open the drawer on the player I can hear the noise of the opening on my speakers 

Are these normal??

I have a pair of Sylvania VT 231. 6SN7GT on my OPPO 105 Modwright and when I open the drawer on the player I can hear the noise of the opening on my speakers

Are these normal??

@zorro

That’s very normal for vintage 6SN7GT in "upstream" slots. That’s why I mentioned I hate these tubes in anything but power amps - where they’re far enough downstream from most of your system’s net gain (gain structure). The problem is:

1. 6SN7 has very LARGE plate structure compared to its moderately high mu / gain
2. Vintage 6SN7GT (and VT-231) are very old, and its large mica spacers are not holding the internal parts as tightly as they should, especially after all these years. Later GTA and GTB variants improve the plate & mica structures for this reason; you might try those though they don’t sound as "sweet" as GT.

And yes, any mechanical switches or motors in the SAME box as a 6SN7 is going to cause audible mechanical feedback. That’s not specific to 6SN7 - I have 6H30 preamps with the same issue (they are very sensitive to this). Tube dampers are worthless for this; don't even bother - the problem is how they are mounted to the sockets and PCB / chassis. 

Anyways, if your Oppo 103 has a digital volume control (I forget if it does or not), and you’re using this to directly drive your amps, your problem is gonna be SO MUCH WORSE. If you had an analog preamp with volume control, then that attenuator is at least able to filter some of the microphonic noise (a downstream attenuator reduces the "net gain" the 6SN7 sees downstream). By contrast, the Oppo’s digital volume occus before the 6SN7, so your tube noise effectively bypasses it.

Frankly, 6SN7 here is a rather sadistic choice on part of the modder.

@acresverde seems as though the Melz tubes have a reputation of having problems. Reading on other forums shows that many of the noise and different failures can be fixed by resoldering the connections inside the pins. I’ve been put off buying them because of the issues people have reported. It would be a shame to throw out expensive tubes if they could be repaired. 

If you want amazing sound but don’t want to spend the big bucks on the really hard to find NOS you have some options. You could use an adapter that allows you to use a pair of 6j5, 6c5, or even 6p5 tubes instead of the 6sn7. The 6sn7 essentially has two 6j5 in one bottle so a pair of 6j5 are exact equivalents of a 6sn7. I really like the Cossor 6c5g, GEC l63, Australian 6j5gt, and the good old metal RCA 6j5.
 

You could also get an adapter that allows you to use 12v versions of the 6sn7. The 12sn7 tubes are exactly the same as the 6sn7 but much less expensive. It’s the only way I could afford the GEC b36, the b65 sells for stupid money these days. Same holds true for the Tung Sol black glass round plate 12sn7. I also use that adapter along with the 6j5 adapter to use 12j5 tubes. Love the Raytheon 12j5wgt, Sylvania round plate 12j5gt, Mullard cv535, and Tung Sol JAN 12j5gt. 
 

The 7n7 tubes mirror the Sylvania 6sn7 tubes for the most part. If there’s a Sylvania 6sn7 you like you can get it for less in a 7n7 with one exception. The original metal base Sylvania 6sn7w is generally considered to be their best but they never made an equivalent 7n7 or even 12sn7. Interestingly, the 14n7, the 12v version of the 7n7 seems to be an exact copy of the metal base 6sn7wgt complete with copper support rod. The 14n7 is one of my most loved tubes and also one of the cheapest in my collection. 
 

There are a few variations of the 7n7 that are worth looking for. Any of the tall bottle ones are good, just like the tall bottle 6sn7. Some say the so-called Frankenstein version sounds better. Its bottle is shaped slightly differently and that’s how you can tell them apart. All of the 7n7 and 14n7 were made by Sylvania with one exception. National Union made round plate 7n7 for a very short period of time. They have a dark tall bottle and you can see the bottom of round plates in the gap between the base and the dark coating. Great sounding tubes, the same as the NU round plates 6f8g as far as I can tell. 

Don’t forget the Shuguang WE6SN7 Plus. This is a fantastic current production tube. I use a pair in my Don Sachs DS2 and they are lovely.

Just thought I would chime in here with my experience. In my system I have a pair of 6SN7s in my preamp and each of my monoblocks uses a 6SN7 in the driver stage.

When I first got my tube preamp it came with late production Russian equivalents - (6H8C? or 6N8P? I don’t remember). They sounded great, but the forums got me obsessed with the old tubes. I read & researched on the various forums and bought a lot of tubes. Yes, there were differences and I eventually settled on a pair of Ken Rad VT 231s as my daily drivers in my preamp. My power amps came with brown base 5692s. When one of those finally failed I replaced them with a pair of coin base Sylvanias that are typically "pooh-poohed" in comparison with the usual, well-respected suspects. They sound fantastic and are probably the quietest 6SN7s in my collection.

Recently I switched the Sylvanias for the Ken-Rads between the power amps and the preamp. They sound superb. I did not expect them to sound so good!

My system has evolved a lot over the last 24 months. And I’ve been able to distinguish the impact of every change, sometimes with grudging acceptance - "this should not make a difference, but I can hear it, and, having heard it, I cannot go back!" It can get expensive!

All this experience has reinforced the "foundational truths" that:

- Everything is system dependent and everyone’s system is different, at least if for not other reason than the fact that our rooms are different. As well as our experience and preferences.

- You can read the various forums and opinions for entertainment value but there is no substitute for personal experimentation and patient, relaxed listening, in your system. Opinions and verdicts about what is best are about as useful as reading a Car and Driver magazine where they test a Ferrari or whatever, but what you need as your daily driver is a Honda Pilot. Or Ford F150 pickup. Entertaining, but, for all practical purposes, irrelevant. At best, such posts can point the way from someone else’s lessons learned in their system, in their room, with their listening preferences.

- We all have our own preferences, largely based on what we're used to.