12at7 vrs 12ay7

[macdillard]

This is my first 5E3 build and I am building it out of parts that I already have..I do not have a 12ay7 for the 1st pre amp tube but I do have a 12at7. Can I use the 12at7 in place of the 12ay7 and if I do are there any changes to the schematic that I have to make.

[Bruce / Mission Amps]

More gain then a 12AY7, probably more plate current resulting in lower B+ at the 100K plate load resistors (maybe try 56K) but it will work OK until you find a 12AY7.

[macdillard]

Thanks Bruce.