My wife coffee shop's amplifier

This Pioneer amplifier working over 15 years.
Fix two times already and always one channel broken.



 
So I buy a tube amplifier on internet.
12AX7 + 6AQ5 + Look-T Opt and diode rectifier with Look-T chock.



 
This Amplifier had been modify so many time.
With Opt second side feed back to 12AX7 cathode bias.




Take off Opt second side feed back to 12AX7 cathode bias.
Modify 12AX7 and 6AQ5 bias and change couple capacitor ...Bennic cap not good.