TUBE GAIN

Yes the 12AX7 will outperform the 6922 in your scenerio. The 12AX7 has a amplification factor of 100 whereas a 6922 has a factor of 33.

GE explains the amplification factor as is the ratio of a small change in plate voltage to the small change in grid voltage when the plate current and all other electrode voltages are maintained constant.

The 7025 is similiar to the 12AX7 (AF of 100). Of course, it will have adifferent signature than the 6922.

THANKS FOR THE EXPLANATION.

If you prefer the gain of the 6922, you can try using 5751 instead of 12AX7. The 5751 is a direct replacement with an amplification factor of 70 (not as low as the 6922 but still better than 100). Besides, all of the 5751 I have tried sounded fantastic.

Arthur

The 12AX7 does have higher output but for the same reason it is also noisier.