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kiteman
November 26th, 2010, 10:33 AM
I'm wondering what gains do inverters do better with or does it change the way the output tubes work?

I had a Chinese 12AX7B in it and I put in a Fender 12AX7 which was a Sovtek 12AX7WC. It seem to sound stronger/louder now, better too.

I have a EH 12AY7 and a Jan Sylvania 12AT7 on hand, will they make some kind of differences?

duhvoodooman
November 26th, 2010, 01:41 PM
As I understand it, 12AY7 and 12AT7 tubes are often used as phase inverters and their lower gain relative to a 12AX7 gives the amp somewhat more headroom. Try 'em and see what you think--certainly shouldn't hurt anything.

Here's some "light reading" for you on what phase inverters do:

http://www.300guitars.com/articles/article-demystifying-the-phase-inverter/

kiteman
November 26th, 2010, 01:53 PM
Interesting site, got it BMed thanks. :)

gndboy
December 5th, 2010, 03:02 AM
Using a 12A()7-type for the driver/inverter gives you some choices. Many folks like another gain stage at this point (louder, more distortion with the 12AX7-type), while others like what the gain stages have already done prior to the phase inverter and those amps use a 12AU7-type or similar. You can pretty much freely experiment with these dual triodes at any point in the tone chain.