ampage Tube Amps / Music Electronics	For current discussions, please visit Music Electronics Forum.

ampage archive

Vintage threads from the first ten years

6CG7 Phase Inverter?

:

9/20/2000 8:16 PM

6CG7 Phase Inverter?

I was wondering, has anyone here used a 6CG7 for a phase inverter? What were the results? I've seen 6SN7's used and I had a homebuild amp that someone gave me that had two 6SN7's for both the preamp and the PI. Would a 6CG7 sound similar? I'm asking because it looks like it would be easy to convert from a 12AX7 to the 6CG7 (pretty much just a change in heater connections).

Chris B

9/20/2000 8:47 PM

Chris,

I've seen the 6CG7 described as "a 6SN7 in a nine-pin bottle", but to me it's always been more like a 12BH7A; kind of like a 12AU7 on steroids. The 12BH7A won't require rewiring the base like the 6CG7 will.

I would think it will work fine for the phase inverter, depending on the PI design. It's kind of low-gain for good balance in a long-tail PI, for example, unless you use a balance pot.

Ray

9/20/2000 10:08 PM

6CG7 = 6FQ7. Great tube. Very linear, popular in the AR line of HiFi tube amps. Among the lowest distortion trin triodes around.

It really is a 6SN7 in 9-pin format. Slightly reduced ratings from the octal version.

The bottle is tall, so standard tube shields will not cover it.

Used in some Silvertone guitar amps too.

Only current production is from Ei. NOS is avaiable and not terribly expensive though not very plentiful. RCA clear tops reguarded by many as the best version.

9/20/2000 10:23 PM
Casey4s	My VT22 uses a 6CG7 for the reverb driver. Casey4s

9/20/2000 11:46 PM
Chris B	I already have two of these at home (NOS) and was just getting ideas for the next amp that I build. Thanks! Chris B

Page 1 of 1