Modding a Morley Diamond Distortion

[davenoid]

I own an out of production pedal by Morley called the Diamond Distortion. I like the pedal except for the tone control. I need to dime the tone to keep the pedal from being too muddy and undefined. Below is the schematic. Does anyone have any ideas for simple mods that will either give the tone control better range (more treble available sooner) or that will make the pedal's overall tone more clear and open?

Any help is much appreciated.

[Fender3D]

Tone control looks like BMP's just with different values...
You may download TSC http://www.duncanamps.com/tsc/ and play 'till satisfied..

BTW
C7 will cut lotsa treble... try and lower it

[Fender3D]

whoa,
the more I look at schematic the more explianing to go...

With distortion units is not always a matter of "adding" gain or frequency, sometimes it's just a matter of balancing gains or frequencies (or both)....

[Mark Hammer]

C7 appears to roll off a LOT of top end.  With C7=2200pf and R8-82k, that's an 880hz rolloff, even before we get to the R9/C8 network.

the tone network is the standard simple highpass/lowpass blend circuit as used in the Big Muff and so many others.  You could monkey around with the corner frequencies of those filter sections, but I'm going to say that opening up the top end, via a change in C7m may do what you want and get something a little more biting in there.

Drop C7 down to 1000pf.  That will raise the limit on how much top end "escapes" from the clipping section.  If it's too much, then that's what the tone control is for, right?

[davenoid]

Thanks for the responses! I will try lowering C7.

[Strange]

Sorry for the bump but I was wondering if the original poster had any luck with a mod for this pedal.

[Gus]

First the tone control is not a "standard" BMP tone control.  Note the tapering resistors from wiper to the ends this makes a difference.

The best thing to do is to sim the circuit and vary the values of the part that adjust the EQs of the effect
C4, C7, C8?(hard to read) sim what R12 and R14 as well as the other resistor and cap values are doing to the "standard" BMP tone control.

IMO it is often better to try to understand what the "design" idea was before changing it sometime this gives an insight to what to change for the sound you want.

[Gus]

I just simmed the circuit and tried a few things.  I did not retune the tone control yet.

two simple changes

1st change C8 to a .1uf film from the 1uf, try the circuit
if not enough change then
2nd lift one side of R9 and C7 leave R8, this removes C7, R9 and C8 from the circuit.  Feedback loop is then just the 82K(you should be stable at that gain 82k/4.7k).

EDIT the schematic looks to have two C8 caps.  The one to change to .1uf is the one before R7  I would guess that should be labeled C6

[sushimandaddi]

Does anyone know what to change to make higher gain? Just to give the gain control more of a range.