Just finished building an electret microphone from this which uses a TL072. I subed a 5pf for the 2pf cap and added resistors to the unused half of the opAmp. I have to wait till the AM to buy a 1/8 plug so I can try it with the computer. It does drive a headphone, sounds clean. Hope it stays that way when I attach it to the computer.
I will be powering the circuit using a 9V battery. A 10K audio taper controls the output level. I would like to replace it with two fixed resistors. Will the output level be fairly flat/steady over the life of the battery? Or do I need to adjust the output level as the battery ages?
I know I can increase the input level on the sound card if the output drops but at some point I think that will result in hiss/noise.
[ just switched to opera and do not have a spell checker working yet...]
**broken link removed**
I will be powering the circuit using a 9V battery. A 10K audio taper controls the output level. I would like to replace it with two fixed resistors. Will the output level be fairly flat/steady over the life of the battery? Or do I need to adjust the output level as the battery ages?
I know I can increase the input level on the sound card if the output drops but at some point I think that will result in hiss/noise.
[ just switched to opera and do not have a spell checker working yet...]
**broken link removed**