PRR-176 Rev 1 Compressor Discussion (Reboot of lost forum subject)

[emx]

Seems the original forum for the revision 1 of the AC Sound PRR-176 was lost or deleted from the forum so, if no one minds, I would like to recreate it here. Surely there are a few of these boards and probably un-operational units still laying around other than the one I ran across and picked up. I believe there are a handful of error corrections that were not stated listed elsewhere and I have some further errors and build tips I wanted to share should I ever get this unit operational. I'll be sharing everything I ran across when I can.

 

[Script]

Ever got it operational?

Here's the BOM for v1.1

 

[duantro]

I got a v2 one off of the black market that I got working. Good luck, It;s really difficult to decipher all of the revisions, etc. Mine sounds great, but oscillates if I use a 1731 and gain it up. might be something goofy with the opamp though.

 

[living sounds]

I got a v2 one off of the black market that I got working. Good luck, It;s really difficult to decipher all of the revisions, etc. Mine sounds great, but oscillates if I use a 1731 and gain it up. might be something goofy with the opamp though.

Make sure the tubes actually get 6.3V heater voltage. It may be necessary to use thicker wire for the heater as well. I had motorboating issues in mine until I got that part right.