Archive
AMZ Q&D Compressor
This is my second attempt at this build, and it is a real winner. I had some trouble with the first build. I think that arose from a faulty SSM2166 IC, a faulty potentiometer, or some other gremlin that I can’t figure out. Rather than give up, I did a second build. All I can say is wow. I need to experiment with it more, but it really seems to just make my basses tone so much more…present, I guess. More reviews to come, but here is the finished project.
A HUGE thanks to Jack Orman at AMZ FX for his willingness to offer advice during the first build. Also, a hat tip to my mates at the diystompboxes forum for their help as well.
Debugging AMZ Q&D Compressor
I put together an AMZ Q&D Compressor. I am having some difficulties and was wondering if anyone can offer some insight.
First – here is the tech page with the schematic – http://www.muzique.com/tech/2166.htm
It seems to work very well, except for the GATE pot. When the GATE pot is cranked all the way up, it works. If the GATE pot is anything less than dimed, I get horrendous feedback and squealing.
I did some voltage testing –
Q1 – 2n5457
D – 9 v
S – 5.46v
G – 4.5 v
U1 – 78LO5
1 – 5v
2 – 0v
3 – 9v
U2 – SSM2166
1 – 0v 14 – 4.95v
2 – .14v 13 – 2.25v
3 – 2.47v 12 – 0v
4 – 2.47v 11 – 4.95v
5 – 2.26v 10 – 1.42v
6 – 2.26v 9 – 4.95v
7 – 1.56v 8 – .58v
D1 – 9v
Other notes: I changed C6 to 10uf, as I play bass, and C8 to 100uf, to address any power supply hum.
If I turn the GAIN all the way down, I can back off of the GATE a bit, but it is all but unusable unless it is fully dimed.
Argh….