Researching Ibanez/Maxon CP101 compressor

[jrc4558]

Hi everybody!

I'm trying to find a schematic for this effect. Any help would be appreciated.

Thanx.

[Mark Hammer]

I stumbled across a Maxon compressor schematic drawn by a Shun Yamazaki at some Japanese site, though the link is lost in the mists of time.

I don't know if it's the same one but it's fairly primitive, and a sort of amalgam of the Dynacomp rectifier circuit and the Anderton compression stage.  The rectifier feeds an optoisolator, and the LDR half of the optoisolator sits in the feedback loop of a non-inverting op-amp gain stage, using a 741.  One op-amp, three transistors, and an opto.  Since it is a redraw, I have no idea if the drawer left off any FET switching stuff and related subcircuits (e.g., input buffer).

[jrc4558]

Thanx Mark! I saw a picture of the board somewhere on the internet. It showed an optoisolator, an op-amp and two transistors. Got me thinking its more like a DOD two knob comp. However I lost the link to the picture and now can't rely on my memory. I think I'm just going through my "compressor stage".

Anyway, here's what I've found so far...
http://www.one-electron.com/FC_ProAudio.html
Not only compressors, but lot's of other stuff too.

[Mark Hammer]

Yeah, I'm aware of that site, and downloaded most of what I thought was interesting.  The lion's share of it is broadcast-quality stuff, and almost invariably has transformers involved, no specs of which are listed, and no examples of which are probably obtainable anywhere.

[jrc4558]

Awareness is ALL!!!