Keeley 4 Knob Compressor Not Compressing

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Keeley 4 Knob Compressor Not Compressing

JP49
I built the Keeley Compressor found here. http://tagboardeffects.blogspot.com/2012/07/keeley-4-knob-compressor.html.

Here is a schematic I found by googling. http://i650.photobucket.com/albums/uu229/MNhutDevil/Keeley_C4_Compressor_schem.jpg~original

I get signal through and everything sounds fine, but there is little to no compression. The sustain pot acts more like a volume knob, but it doesn't completely kill the signal when fully turned left.

I've double checked for solder bridges, and reflowed in a few areas just to be sure. I checked the voltages against a post I found on diystompboxes.com. Everything was pretty close to what it should be except Q1 and Q2. Any help or ideas of what to check would be appreciated!

My Q1 And Q2 Voltages


Q1

C 7.2
B 1.45
E 2.05

Q2
C 6.74
B 2.89
E 2.75

Correct Voltages


IC1

1.   NC
2.   4.6
3.   4.6
4.   0.0
5.   0.7
6.   2.7
7.   9.0
8.   NC

Q1

C  6.6
B  2.8
E  2.2

Q2

C  6.9
B  2.7
E  2.1

Q3

C  8.9
B  0.0
E  0.0

Q4

C  8.9
B  0.0
E  0.0

Q5

C  9.0
B  8.9
E  8.4
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Re: Keeley 4 Knob Compressor Not Compressing

Ciaran Haslett
Q1 the wrong way round?

The Emitter should be 1 diode drop (0.6ish volts) below the base...not above.
DCA
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Re: Keeley 4 Knob Compressor Not Compressing

DCA
In reply to this post by JP49
I have the same problem, I do not have compression and my sustain does volume. did you solve it?

Thank you