Mangler to bonamassa spec?

[Jmilla]

Currently comparing the schematics and trying to figure out correc component values for Joe bonamassa ff due to differences in designs. What I have come up with so far is r2 to 45 k and r4 to 332r. Does this seem right? Also trying to figure out bias and r3 values given the bonomassa uses a 220r in r3. If anyone would be willing to help me clarify I would be super appreciative.

[WormBoy]

What schematic are you using for the Bonamassa fuzz? The one I see with Google has a trimpot + fixed resistor for both Q1 (R2 in the Mangler schematic) and Q2 (trim+R3 in the Mangler). R3 works together with the trimpot to set the bias for Q2. The 'right' value for the bias resistance depends on the transistor used, so a trim pot is a good idea there (and taking a different value for the fixed resistor only changes the range of the trim pot). Finding the 'right' transistors for this version is probably the trickiest part, and likely has more effect on the sound than small changes in the resistor values ...

[Jmilla]

Ok that's what I was thinking, I have some mil spec It308v from chrome that are pretty similar with correct gain for the bonamassa version. I think my confusion is coming front the single trim pot on the mangler vs the 2 on the ff schematic.

[WormBoy]

The trim pot in Q2 is pretty much needed IMO, also because bias will shift with temperature (and who knows what more). It doesn't hurt to put in a trim on Q1 as well, it will only give you more options to tune the circuit to your taste. If you like tweaking, that is ...

[Jmilla]

Thanks for the help!