Tonestack help

[fixr1984]

I have Marshall AVT head that I've been using. The clean channel has a decent tone
but the OD channel is very muddy. The channel could definatly use more mids. ( From what I hear
this is a common complaint with this amp) Below is the schematic of  the OD tonestack.

I took C79 and lowered it to a 10n. That seemed to help a little bit but I still have to have all the tone controlls
all the way up to sound good.

I guess my question is did I change the right cap? Should I also change any other caps to compenstate?
I can provide more of the schematic it needed.
Thanks for any help.

[Ben N]

Do yourself a favor and download Duncan's Tonestack Calculator. Select the Marshall tab, plug in your values, look at the resulting curve and see what you want to change. Then try different values and see what it does to the curve, and answer your own question.

Just for the heck of it, I plugged your stock values in there--whoa, that is some low-mid hump you got there, at least with all the controls flat. However, you should be able to get something like a flat frequency response from about 100hz out to 10khz by turning the bass all the way down, setting mid to about 6 and treble to a bit over 4. Your change to C79 seems to start gently rolling bass off a bit higher, at about 200hz, but otherwise not much change. Check it out.

Happy New Year!

[bumblebee]

Do yourself a favor and download Duncan's Tonestack Calculator. Select the Marshall tab, plug in your values, look at the resulting curve and see what you want to change. Then try different values and see what it does to the curve, and answer your own question.

I second that!

[fixr1984]

Thanks for the link. That will help a lot. I've been messing with it on and off today
trying to figure out what I want.
Now if i can figure out just what I want.