and... how exactly do I do that?You need to change the input to a cascade circuit to get the jcm feel not the negative feed back
Legendary tones hot mod v2 if you’re after more gain , well more everything really .ok! what mod do you recommend for this amp?
People need to read with more attention.
If you allready have a jmp2203 you have the same circuit as a jcm800 2203.
Later 800s have higher voltage and fewer caps but arranged for same capacitance and a 100 pF cap across anode/ cathode on the input stage, taking the highest highs down a bit.
Enjoy your amp... many people are envious of what you've got....
Thanks!
What tone/feel are you looking for out of the mod? I can help you but I’m not sure about the mod you are speaking of. Lowering the resistor value will increase the negative feedback and make the output section less aggressive up to the point of breakup. I don’t know how hard you push the power section, it’s 100 watts so it’s powerful. Using a smaller resistor will also increase the amount of presence. You’ll have to adjust to taste. Increasing the NFB resistor will make the amp more aggressive and reduce the presence.Well, originally I was interested in doing the NFB mod but I don't know which resistor to change and what value should I use.
Like someone mentioned above me, I wouldn't mod this amp. It's worth more stock then what you want it to do. If your not into it, I'd sell it and buy what your looking for.Hi,
I have a Marshall JMP Master Model 2203 MK2 100watt and want to do the negative feedback mod. Which resistor on the board should be changed? and What is the recommended value to get a JCM800 feel?