Author Topic: Colorsound Fuzz Phazer issues (schem inside)  (Read 538 times)

disorder

Colorsound Fuzz Phazer issues (schem inside)
« on: December 14, 2019, 07:36:35 PM »
I got one of these bad boys in a trade, and I couldn't find a schematic for it online so I traced it myself. The unit has two issues, first is real weak phasing the second is bad radio interference and idle hiss/crackle especially when the fuzz is engaged.

Schematic: https://imgur.com/a/Wo5MLLi

It seems to be a manually controlled phaser (the dual gang pot that you control with your foot modulates two phaser circuit stages) with a fuzz circuit you can tack on with the push of a switch.

I have two questions about this circuit. First, when I took the pot out to test it, the two gangs are pretty mismatched. It's a 100k linear dual pot, I measured one gang max resistance as 180k and the other as 140k. So not only are the two gangs very mismatched but the are nearly 50-100% out of spec. Based on the schematic should the two pots be matched in a way that FETs would be matched for a Phase90 circuit?

Second, assuming I checked all ground connections, is it safe to assume the fuzz circuit in this is so high gain that radio station interference might be inevitable? Could I take on a cap to ground at the fuzz circuit input?

duck_arse

Re: Colorsound Fuzz Phazer issues (schem inside)
« Reply #1 on: December 15, 2019, 08:50:56 AM »
not terribly helpful, but from your dia, it looks like "a" fuzz face and a pair of magnavibe-type stages - really just phase splttters with the ldr/vdr replaced w/ pots. the mismatch between the stages shouldn't really be a problem if the pot is ok, but it looks very much like a not-for-wah type of pot from googoo photos.

is the base bias divider really 4k7 over 1M?
.... adding a bit of "supplementary hair" ....

cushychicken

Re: Colorsound Fuzz Phazer issues (schem inside)
« Reply #2 on: October 15, 2020, 12:52:15 PM »
Heya - WAY late to the party here, but I'd be interested in the schematic trace of that Solasound Fuzz Phaser if you still have it. The imgur link no longer works.