feedback resistor/diode help in ff clone needed

[CoolJohnny]

building a fuzz face based on the multi-face post. in feedback loop between base of Q1 and emitter of Q2 the schematic calls for 150K resistor. this offered far to mild a sound so i started increasing the resistor, and got all the way up to 1 meg before it got out of control. just have to adjust the 10k trim pot accordingly.

got some seriously sick sounds out of my bassman with this arrangement. champ clone couldn't handle it.

my first problem is this. i'd like to install a gain pot here. seems a good way to control the amount of fuzz. i figured putting a 1 meg pot parallel to the 150K resistor would do the trick....it doesn't. no bizzare combination of pots and resistors gave me what i was looking for. is this a possible mod even, or is there some cardinal rule of resistence i keep breaking?

secondly, no matter where or in what arrangement i put a silicon diode pair, it seems to cut back on the output volume considerably, is this supposed to happen. i've done this with many other fuzzez/boosters and have not yet come across this problem

any help appreciated folks. keep your irons hot ...

[Ge_Whiz]

First of all, putting a pot in parallel with the 150k resistor, irrespective of its value, will only decrease the 150k. To increase it, as you described in your first paragraph, the pot will have to be in series.

Secondly, clipping diodes do just that - they limit voltage levels to typically +/- 0.7 V (for silicon). If you put them in a section of a circuit that normally carries a higher voltage, you limit the gain and and hence the output at that point.