[BossaNova31]

I have Ken Rad VT231, RCA VT231, RCA GTBs and new production TungSol 6SN7s for use in my 300b amps. My overall favorite is the RCA VT231 

[jimdgoulding]

Have a question, need help really, moved it to Pre amp tubes.  Thanks.

[ndeslions]

I have Ken Rad VT231, RCA VT231, RCA GTBs and new production TungSol 6SN7s for use in my 300b amps. My overall favorite is the RCA VT231 

Because you have a bright system 

[JakeJ]

I have the following in my stash:

Sylvania VT-231/6SN7GTA short bottle w/ top getter
Sylvania VT-231/6SN7GTB tall bottle w/ top getter
GE 6SN7GTB short bottle w/ side getter
Tung-Sol 6SN7GTB tall bottle w/ top getter
RCA 6SN7GTB mixed bottles w/ both top and side getters
RCA 5692 brown base w/ top getter

So far I like the Sylvanias in my VAC PA-160 amps.

I have four or five sleeves each of the GE and the Tung-Sol.  I should sell a few so I can try others.

Jake

[vett93]

My understanding is that VT-231 was the naming in the '40s. GTA/GTB are much later. So I am not sure what VT-231/6SN7GTA means. I have yet to find a GTA/GTB that has as much air as VT-231 or 6SN7GT. These GTA/GTB tubes sound a bit dull in the 3 sets of sources/amps/speakers I currently own.

I have more than 100 tubes of various 6SN7 variants in my collection. But I still can't find the best one for all my systems. It seems that they all have their strength and weakness. For example, Sylvania VT-231s are dynamic, full of air, but its mid-range is a bit over emphasized. I love the timbre from RCA grey-glass VT-231s. But its bass is a bit loose. Ken-rad dark-glass 6SN7GTs have great bass but I don't think they are as dynamic or have as much air.

These 6H8Cs with metal base and hole plates surely sound good in my Counterpoint NP100. But they sound a bit brittle in my other gears. BTW, 1578 is the plant number, not the model number.

So what is the best 6SN7? The search is still on.... 

[Frihed91]

The sleeper is the Tung-Sol VT-99 tube.  It requires an adapter.  Check on Ebay.  The adapters are sold by a guy in Tawain.  Bunes Aires Radio sells the Tung-Sol VT-99s.  This is the most linear 6SN7 type I have.  I also like the 7N7 which requires a loctal to octal adapter.

[JoshK]

VT-99 = 6F8G

Said to be a good *SN7 type.  I have a bunch of 7N7s.  Morgan Jones ranked the 7N7's high in his tests. 

[ecramer]

The sleeper is the Tung-Sol VT-99 tube.  It requires an adapter.  Check on Ebay.  The adapters are sold by a guy in Tawain.  Bunes Aires Radio sells the Tung-Sol VT-99s.  This is the most linear 6SN7 type I have.  I also like the 7N7 which requires a loctal to octal adapter.

Dan'g nabit i would need $100 worth (4) for my pre 

http://cgi.ebay.com/one-Adapters-6F8G-TO-6SN7-tubes-SUB_W0QQitemZ250410270041QQcmdZViewItemQQptZVintage_Electronics_R2?hash=item3a4d9d7d59&_trksid=p3286.c0.m14&_trkparms=72%3A1205|66%3A2|65%3A12|39%3A1|240%3A1318|301%3A1|293%3A1|294%3A50

[jkelly]

I have always appreciated the VT-231's!

[Lizard_King]

I have 60's GE black based 6SN7s.

[JoshK]

I just got around to testing my 6sn7 collection on my Hickok 752.   I was quite pleased to see that most tested as new.  I got a lot of nicely matched pairs.  I mostly have a bunch of GTB's but I also have two pairs of GT's. 

I had gotten about 10 pair in a $50 box from a fellow ac member some 5 years ago, untested, unboxed and mostly pretty dirty.  One was DOA, one tested well but was really gassy (no problem, can fix that) and the rest tested as new once the pins were cleaned. 

Sometimes it pays to take a chance.

[Frihed91]

The 7N7 is indeed a very good tube to my ears.  My favorite actual 6S7GT would be a Raytheon I or II and the 7N7 is right up there. The Sylvania 6SN7W is also a favorite as a driver, (it is very neutral), also the 1578 and of course the VT-99.  I I like so many of these tubes...but not the TSRP, for some reason.  It just doesn't float my boat.

[Niteshade]

Josh-

What is your method for fixing a gassy tube?

[JoshK]

I've read a few ways to do it, but most involve heating the tube for a couple hours with no signal.  You can then also hit the tube with some signal, I'd suggest a low Z source, like a mosfet follower (that can provide the grid current a gassy tube will demand). 

Essentially this is said to burn the gas before it is placed in circuit.  May not work for all tubes.

[JamesFox777]

Have you tried the 12sx7?

Yes .. RCA's and my most favorite : 12SX7GT GE Canada, in the par with a VT231 Tungsol round plate !!