card9inal:
Lefty...This is not a specific Arduino project, although I'm trying to get my Arduino to interface with this.
This will be a pre-amp that will be mixed with another signal and end up in headphones after some switching (where the Arduino might come in). The rest of the circuit works great, but I'm trying to build my own pre-amp as it will significantly help keep the space in my enclosure at a manageable level, and limit the number of power supplies going into this box which is a huge concern since I have to travel this thing across the country while being checked as luggage on an airline, and you all know how they can be with luggage and weight!
I think my problem was answered, but I have to try it tomorrow... I realize that I didn't use it as a differential amp. DVDdoug, thanks for pointing that out. It had nothing to reference the signal against.
I spent quite a few years collecting and repair vintage 1970s classic solid state hi-fi equipment. Anyway while in the hobby I found a great site for audio circuits, most have outstanding performance and very easy to duplicate. Elliott's site has tons of good information and is great for just general electronics. See the section covering mike amps:
http://sound.westhost.com/projects-0.htm#mic
There is even a 5532 based one.
Lefty