Ab165 bassman

[Colestrat]

Hello all I’m new to the forum and in a couple of weeks I’ll hopefully be purchasing an original 1966 AB165 bassman head, I was wondering if it’s possible to convert the amp to the more desirable AA864 circuit and if someone could give me a detailed plan of modding the amp, the amp is functional but is in dire need of some tlc and I only plan on modding it’s to the AA864 circuit if I don’t like the AB165 after it’s been repaired.

[martin manning]

Google is your friend: https://www.thegearpage.net/board/index ... x.2194308/

[ChopSauce]

That 500pF in series (inline?) on the signal transmitted to the phase inverter, right after the connection between both normal and bass channels seems weird, especially on a bass amp, isn't it?



Anyway, I think I spotted at least one difference between this schema and another usual one for the AA864(*) - to be taken "with a grain of salt", as usual -
(example given: the 220k on the bass channel should be before the connection)
_

(*) https://ampwares.com/schematics/bassman_aa864.pdf