Hi
If I've got the following 2 circuits in the same box would it be best to bias both op amps non inverting inputs from the same resistors rather building both complete circuits and only sharing + volts and ground ?
Here's the mic pre :
http://circuitswiring.com/circuit-diagrams/0/2011/10/electret-microphone-pre-amp.jpg
Heres the headphone amp :
http://www.redcircuits.com/Page119.htm
The reason I'm asking is with the circuits only sharing + volts and ground I'm getting motorboating in the cans when the electret mic is connected to the pre amp via a capacitor, which I need to do to keep DC out of it's volume pot which isn't shown in the schematic but mic hot is to one end of pot, ground to the other and the centre wiper goes to input of amp in normal way
Thanks in advance
If I've got the following 2 circuits in the same box would it be best to bias both op amps non inverting inputs from the same resistors rather building both complete circuits and only sharing + volts and ground ?
Here's the mic pre :
http://circuitswiring.com/circuit-diagrams/0/2011/10/electret-microphone-pre-amp.jpg
Heres the headphone amp :
http://www.redcircuits.com/Page119.htm
The reason I'm asking is with the circuits only sharing + volts and ground I'm getting motorboating in the cans when the electret mic is connected to the pre amp via a capacitor, which I need to do to keep DC out of it's volume pot which isn't shown in the schematic but mic hot is to one end of pot, ground to the other and the centre wiper goes to input of amp in normal way
Thanks in advance