Hello , I'm wondering since I can't find an explaination on-line and don't have any tube manuals . What is the difference between 6sn7 gtb, gta , gt and so on ? I just won two NOS 6sn7gtb's on that popular aution website. I think I got lucky because these things are getting expensive. Many thanks

:Hello , I'm wondering since I can't find an explaination on-line and don't have any tube manuals . What is the difference between 6sn7 gtb, gta , gt and so on ? I just won two NOS 6sn7gtb's on that popular aution website. I think I got lucky because these things are getting expensive. Many thanks
:according to my sam's tube book,there is no diff.

Andrew

Very little difference. 6SN7GTA and GTB have some improvements. Controlled warm up for use in series wired filament TV's (GTB) and higher ratings for Vertical Deflection Amplifiers in TV (GTA & GTB). The 6SN7GT was used in the same circuit prior to the inprovements.

Norm

:Hello , I'm wondering since I can't find an explaination on-line and don't have any tube manuals . What is the difference between 6sn7 gtb, gta , gt and so on ? I just won two NOS 6sn7gtb's on that popular aution website. I think I got lucky because these things are getting expensive. Many thanks
:

:Andrew
:
: Very little difference. 6SN7GTA and GTB have some improvements. Controlled warm up for use in series wired filament TV's (GTB) and higher ratings for Vertical Deflection Amplifiers in TV (GTA & GTB). The 6SN7GT was used in the same circuit prior to the inprovements.
:
:Norm

You can always go higher (B instead of A) but I would not go backward, especially in a series filament TV.
Lewis
:
:
::Hello , I'm wondering since I can't find an explaination on-line and don't have any tube manuals . What is the difference between 6sn7 gtb, gta , gt and so on ? I just won two NOS 6sn7gtb's on that popular aution website. I think I got lucky because these things are getting expensive. Many thanks
::
:

Hi Andrew,
I recall talking with TV repairmen when I was a kid that 6SN7 tubes all differed from one another. The would go to a house where the TV was rolling as they used to do. They would then try 6SN7 tubes one after another until one stopped the rolling.
All the tubes test good, even the one originally in the set.

Best Regards,

Bill Grimm

This is typical of tubes and television in most cases. Televisions are very picky concerning tubes.

T.

And, speaking of 7 watts, one is used as a push-pull output on one of my Webster Chicago wire recorders. It certainly adds a lot to the fidelity of the machine (what fidelity a wire recorder can have), and has quite a bit of power reserve.

T.

Hi Thomas,
This is the first time I have heard of 6SN7GT used in something other than a television. Were they ever used in radios?

Best Regards,

Bill Grimm
:And, speaking of 7 watts, one is used as a push-pull output on one of my Webster Chicago wire recorders. It certainly adds a lot to the fidelity of the machine (what fidelity a wire recorder can have), and has quite a bit of power reserve.
:
:T.
:

Bill

Not as common as TV's but they were used in some radios and audio amps. Usually as audio amplifiers and phase inverters to drive push pull.

Norm

:Hi Thomas,
: This is the first time I have heard of 6SN7GT used in something other than a television. Were they ever used in radios?
:
:Best Regards,
:
:Bill Grimm
::And, speaking of 7 watts, one is used as a push-pull output on one of my Webster Chicago wire recorders. It certainly adds a lot to the fidelity of the machine (what fidelity a wire recorder can have), and has quite a bit of power reserve.
::
::T.
::
:

Most Webster Chicago wire recorders have 6SN7s, either as a pre-amp or as an output, depending on the model. The original tubes are made by Ken-Rad.

My 1949 Zenith FoMoCo (Mercury) radio uses a 6SN7 as a phase inverter for the audio. I have also seen them used in guitar amplifiers.

T.

Thank you for the responses, Thomas and Norm.

Best Regards,

Bill Grimm

Here's the audiophile explanation ...

http://www.audiotubes.com/6sn7.htm

I have a pair of NOS 12SN7s (same as 6SN7 except for the heater voltage). I'm wondering about using them to build a low-power stereo amp. Since these tubes are twin triodes, I could use two sections for a preamp stage and the other two sections as single-ended output stages.

Here's sort of the idea, but I'd hope to scotch the solid-state output and go straight from the 2nd 12SN7 stage as the audio output.

Whoops - here's the link: http://www.laud.no/la6nca/homebrew/6sn7.htm