Help with the circuit in my Echoplex?

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JW

Well-known member
Joined
Jun 8, 2005
Messages
1,100
Location
Portland USA
I bought this Echoplex EP-4, and the guy said it's one of the more rare EP-4's with a compressor circuit in it. What I've heard is that it sounds better if you bypass the thing, and listening to it, I definately would prefer if the compressor wasn't doing what it's doing.

I'm wondering how to by-pass it though. I took some pics here, and I'm wondering if you guys could help me out. My guess is that the circuit board on the left is the compressor.

It looks like I can just take the gray wire that's coming in from the input jack and solder it to wherever the compressor connects to the main board on the right. The problem is, I'm not really sure where that is.

I also took 3 couple pictures with my finger indicating wires that I'm not sure about. A couple are coming from one or another of the pots. There's a little purple wire that connects the two boards. I'm not sure what it is.

Anyway, any pointers would definately be helpful.
Thanks,
Jon

http://img125.imageshack.us/my.php?image=34ri.jpg

http://img125.imageshack.us/my.php?image=14eh1.jpg

http://img125.imageshack.us/my.php?image=29xh1.jpg

http://img158.imageshack.us/my.php?image=42iw1.jpg
 
That's a commercial product?

Alleged schematic of the non-compressor version here if it helps: http://www.schematicheaven.com/effects/ep4.pdf

We might be able to help more if you gave us the order of the knobs and jacks from left to right in your photos.

The purple wire is probably power or ground to the compressor board.
 
[quote author="Boswell"]That's a commercial product?[/quote]

Yeah, it is pretty messy in there. It looks like it has had some work done on it, not very well either. It is a plain ol EP-4 echoplex. I went through the details in the other half of this duplicate post.

adam
 
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