[rosgr63]

Also, about 100 posts back on this thread you thought about making a adapter that up regulates heater voltage (6.3 to 12v) to allow use of 12sn7 s in 6sn7 amps. Did you ever do this? It would likely sell like hot cakes!!!!

 
Glenn makes these adapters, but his amps can be built with a 6/12/25V switch so you can use any of them.
 
The CBS 6SN7GTB is a very nice tube as Rob mentioned above.

 

[gibosi]

  The CBS 6SN7GTB is a very nice tube as Rob mentioned above.

 
In the 6SN7 Reference thread:
 
"CBS/Hytron 6SN7GTB
[black bases, red labels, side getter]
These tubes are rebranded GE 6SN7GTB tubes"
 
Are they rebranded GE's?

 

[2359glenn]

Also, about 100 posts back on this thread you thought about making a adapter that up regulates heater voltage (6.3 to 12v) to allow use of 12sn7 s in 6sn7 amps. Did you ever do this? It would likely sell like hot cakes!!!!

I have already made this adapter but the amp has to be running the 6SN7 off AC.
If you can take a reading 6.3 volts AC or close.  It will not work on a amp running the 6SN7 on DC.

 

[MMMan]

Not sure what the mystery is here. This is a CBS 6SN7GTB. Nice little tube.

 
Thanks. There were no date or manufacturer codes, and I didn't have anything to compare this to. Nice to know it is a real CBS, by CBS!!

 

[MMMan]

Ha!  I knew I wasn't crazy.  The second I saw it I thought "that looks like the photo of Rob's tube closet."  

What a cool idea.

Yes, that is the first thought that entered my mind too!!!

PS - yes, I'm doing my homework... Reading the entire thread from the start...

 

[Rossliew]

Is the CV1988 a direct replacement for the 6SN7 tube? They sure are expensive!

 

[punit]

  Is the CV1988 a direct replacement for the 6SN7 tube? They sure are expensive!

To the best of my knowledge & experience, Yes. I bought mine for $ 140 about 3 months back. How much did you see them for ?

 

[Rossliew]

 
To the best of my knowledge & experience, Yes. I bought mine for $ 140 about 3 months back. How much did you see them for ?

I just did a random search on eBay and the listings were for $200+ for pairs...must have been inflation peaking recently..

 

[Lorspeaker]

If the base of a tube is slightly loose, what is the best/safe way to fix it ?
plaster/superglue/ what can withstand the heat ?
 
( when i insert the tube, sometimes it didnt light up, if i give it a slight touch on the base, it will work)

 

[punit]

  If the base of a tube is slightly loose, what is the best/safe way to fix it ?
plaster/superglue/ what can withstand the heat ?

Try clear nail polish, I tried it once it worked (altough I couldn't be bothered to go buy a bottle of clear NP so I used a red one which my wife had). I think someone on head fi had recommended it  few months back but can't remember who.
 
edit: got it
 
http://www.head-fi.org/t/410326/for-6as7g-tube-rollers-here/1170

 

[Lorspeaker]

Thanks Punit,
tried it a while ago, think it is working...
not exactly clear polish...with some silver dust

 

[Oskari]

  Are they rebranded GE's?

 
That is a fair question. The side getter and the (sometimes) stencilled-looking type number are very GE-like. On the other hand, the plate structure is very Sylvania-like, and GE used ladder plates in their GTBs. (Only ladder plates?)

 

[punit]

  Thanks Punit,
tried it a while ago, think it is working...
not exactly clear polish...with some silver dust

hmm...you audiophiles have to put silver in everything ....

 

[Glam Bash]

Intriguing, I would have guessed Sylvania because of the angled plates. I just assumed CBS got gobbled up by a bigger company by the time the 6SN7GTB "rolled" around.

 

[gibosi]

I find the early CBS/Hytron 6SN7GT to be quite a nice tube, but as the 6SN7 Reference thread suggests that the later CBS 6SN7GTB are GE rebrands I have simply ignored them. As it now appears that these red label GTB's may not be rebrands, I think I should give them a try.