Thanks for reading in, I have a question regrading a MArshall combo that I have upgraded and tweaked and have thoroughly enjoyed and is sounding great.. I have to thank Martin M, Sluckey, and others who have chimed in to help me understand whats going on and how things work etc.. I got there with lots of testing by ear and have arrived at a really nice sounding amp and more what I wanted it to be being the main goal,.. so thanks everyone.
I just have one last thing I want to try and was hoping someone could advise me what is going on with this part of the circuit.. Basically I want to pull out some more 'overengineering' that I found was rife in this amp.. but I don't kbow if these parts are for stability/oscillation, that one might not hear by ear....
One is what Ive found online is nicknamed a 'fizz cap' between the PI plate resistors.. It is (C94) here a 47pf ceramic... Would this be safe to remove??
The main thing however I'm interested in is this resistor (R132, 2M2) in series with another 47pf ceramic (C110).. these are 'bridged' the between the phase inverter outputs that feed the EL84 power tubes.. after the 220k mixer resistors. I'm wondering what the function of these parts are in this circuit and looking at classic amp schematics from Marshall/Fender/Dumble etc.. there is nothing like this present.. Is there any way this could be important in this circuit for stability?? I'm just thinking there is stereo Master volume pot following and maybe this could be something to do with keeping each side of that stable/isolated??
Just trying to remove all the unnecessary stuff in the amp, so far so good! I took out the snubber on V1 as well as the 10nf bypass filter caps straddling the electrolytics on the B+ (Come on, its a guitar amp!!!?)... good results from that, much more raw
Thanks for reading again everyone and whatever you reckon I appreciate your thoughts or experience.
Cheers