Maestro MPF-1. Only clean sound

[kaycee]

Ey kaycee, what was your problem with this build? My only problem is the signal not being boosted. It's at unity or so levels. The rest works ok.

Its quite a while since I had a go at this, but I think I got some output, maybe it went dead in one of the modes? So I can't say I had same issue as you.

I didn't go as far as all voltages like you. I counted holes per strip, continuity tested between strips, got my resistors out and checked values against build and then with meter to make sure I hadn't bagged wrong values, went through with audio probe as much as I could. After I've been that far, I'll generally call it and move on, or just make up another board if I'm really keen. For a circuit this size, I'd much rather build on a PCB.

I admire your persistence. I think it should work stock though, the various clones about, don't seem to be modded for gain.

[iainpunk]

i think most clones are based on actual units, not on the schematic, and Maestro is known to put wrong resistance values in schematics for some odd reason...

cheers

[nonost]

I don't know about other effects but you can find the original schematic by the very Maestro. I think I found it in this forum  but can't find it now. It provides good technical information.

BTW, aren't the broad and med modes reversed in the Mark's layout? According to this layout the middle position is the med one but it sounds as the broad to my ears. Would swapping the mini switch wires do the trick?

[iainpunk]

i know there is an official Maestro service manual, but the schematic is not the same as the real unit, one or two values changed:
http://www.synfo.nl/servicemanuals/Maestro/MAESTRO-PARAMETRIC-FILTER_SERVICE_MANUAL.pdf

i think they do that to keep cloning at bay, or some other reason i can't come up with. there are more companies doing that tho...

cheers

[antonis]

https://www.flickr.com/photos/76376621@N04/46193734785/in/photostream/lightbox/

[nonost]

I see...Which are those values that changed?

The pic linked by antonis belongs to the manual I was referring to.

I see this pedal as a secret weapon. You can dial into some real good and unique tones just turning the freq. pot. Highly addictive.

[iainpunk]

i don't know for sure which values are changes, but that's the point, i guess. DOD has a few wrong schematics as well in their service manuals. the odd thing is that the changes are minor enough to trouble shoot, but big enough to not be cloneable

i suspect the resistors mentioned in earlier posts are off.

cheers, Iain

[aelling]

Check the link/jumper in the red circle vs the one you made on your board.