**HELP**. Egnater M4 Question

[mfred]

I just purchased a used Egnater Dual Channel M4 Preamp. My question is there are two tubes in the main chassis. (From the Back, Upper Right- Lower Left Diagonally). My unit came with two JJ 12AX7A tubes installed. Is this the correct tube for my unit? I read somewhere that one was supposed to be a 12AT7. Please help

 

[Burlo]

Has nobody ever responded to this? !

 

[j4q0]

They're both 12AX7.
You can use a 12at7 on the input tube (bottom one) if you want toblower the gain on the first stage since that tube is V1.