This is a really great little compressor from John Hollis. Follow the guide here to build it yourself. Check out this post to get the background on this project and learn about compressors.
|D1||Ge * see notes|
|D2||Ge * see notes|
|D3||Ge * see notes|
|D4||Ge * see notes|
|LED/LDR||VTL5C3 * see notes|
- Diodes – The original circuit shows Germanium diodes. I had better luck with silicon 1N34a workalike types which are silicon. I suspect this circuit will work with almost any type of diodes. When I used Germanium diodes I was hearing some op-amp clipping. Changing to silicon diodes the noise went away.
- R9 – There is no R9
- LED/LDR – I used a VTL5C3. Seems a lot of people have success with this part. The key seems to be using an LDR with a slow decay time. Check out this post for more info. Works best with a LDR that has a large light history. The decay time of the compression is determined by the decay time of the LDR. You want an LDR with a long decay time.
Use these wiring diagrams.
Here is a drilling guide you can use. It is sized for a 1590B enclosure.