Would anybody please like to take a look at the attached schematic and tell me whether I'm going to get mild smoke, or a real explosion?
The big mystery for me centers around R3 and R4, feeding the output buffer IC2B. I'm not sure what their values should be, or the values of pots Rmic or Rline, or the value of resistor R2d.
The purpose of this preamp-mixer is to feed an electret microphone's amplified output to a computer's line-in. The auxillary line-in is so that a line-in will still be available when the mic is in use.
As you see, the whole thing is built of nearly identical TL072 modules. I kinda think I have these correct, possibly.
I'm using only the +12 volts from the computer power supply, even though there's also about 1/2 watt of -12 volts available. This is because...well, I wanted to see how that would work.
Any help or comment will be greatly appreciated.
The big mystery for me centers around R3 and R4, feeding the output buffer IC2B. I'm not sure what their values should be, or the values of pots Rmic or Rline, or the value of resistor R2d.
The purpose of this preamp-mixer is to feed an electret microphone's amplified output to a computer's line-in. The auxillary line-in is so that a line-in will still be available when the mic is in use.
As you see, the whole thing is built of nearly identical TL072 modules. I kinda think I have these correct, possibly.
I'm using only the +12 volts from the computer power supply, even though there's also about 1/2 watt of -12 volts available. This is because...well, I wanted to see how that would work.
Any help or comment will be greatly appreciated.