6GH8A any good?

[Jonas]

I have a small collection of random tubes, one of which the 6GH8A. This is a 9 pin preamp with a pentode and triode section. 

https://frank.pocnet.net/sheets/135/6/6GH8A.pdf

Would this make for a good preamp? A couple ideas would be pentode -> triode cathode follower, pentode -> triode plate, OR triode plate -> pentode...

What are your thoughts?

[johnnyreece]

My notes say it's in several old Univox amps.  Good replacement for a 7199 (with different pinout!), and much cheaper/easier to find. 

[astronomicum]

My notes say it's in several old Univox amps.

I am not aware of any and would be very interested in knowing which ones?

[johnnyreece]

My notes say it's in several old Univox amps.

I am not aware of any and would be very interested in knowing which ones?

Good call!  Looks like my notes were mistaken.  Univox used the similar-but-different 6AN8.  My apologies! 

[kagliostro]

However the 6GH8A is considered a feasible/good substitute for the 7199 tube (with different pinout)

So to use it you can look to schematics that uses the 7199 tube


Franco

[passaloutre]

I used the 6AN8 recently in a Kay 720 build (https://el34world.com/Forum/index.php?topic=33360.0). It's (the 6AN8) is very similar to the 6GH8, except that the 6AN8 has less gain (af=21) in the triode than the 6GH8 (af=46). Since I used the triode as a cathodyne splitter (gain=1), these two tubes would be sensibly equivalent in this circuit (except for the pinout), as the pentode sections have the same specs. I quite like the tone of this amp, which I attribute to the pentode-triode phase inverter and I plan to use it again.