Is adding an extra filter cap node necessary for an AB763? There's more...

[Ibanezgrind]

Greetings,

I am sure this is an easy question for the pros on this forum to answer. A thought came across me a few days ago and in need of some understanding. I have learned that blackface amps have 6 triodes on 1 filter cap in the preamp and can operate just fine since both channels by design aren't used at the same time.

However, if I wanted to link the channels together in this manner (please see attachment), does this mean it is ideal to have another filtering node in the preamp? If so, where would this be ideal? Would this cause "motorboating" if modded without the extra filter cap? Maybe this is more critical for high-gained amps to which why this mod can get away from doing this for this particular amp.

I keep going back and forth on this. I would appreciate any knowledge on this subject!

[shooter]

solder n see 

guessing whoever "made the mod" did just fine, otherwise it would be called out in the mod 

[pdf64]

... both channels by design aren't used at the same time...

The reason old amp design have 4 inputs is to allow 4 musicians to use the amp. The expectation was that everyone would share the amp, similar to how a PA might be used now.
Speaking of which, the amp would serve as PA too.

On Hendrix’s 1st full tour of the UK, he and Noel Redding plugged into the same Marshall stack.

Those BF Fenders manage ok with several gain stages in cascade sharing a HT node because there’s lots of interstage attenuation, the max overall effective gain is low.

[Ibanezgrind]

Thanks guys for your responses. pdf64, good to know some history there of different situations of a guitar amp's uses. Cool stuff!