Hi, I am constructing the tone control circuit that is attached. Ignore the +/- 28V lines, they feed the amplifier this runs into. The 50K balance pot runs to the same point on an identical circuit below for the right channel.
I am constructing it on a breadboard at the moment, and I've got as far as the 10R resistor coming out of the first op-amp. I'm periodically testing the audio signal that comes out with a small piezoelectric sounder to check that I haven't made a mistake in the circuit. Testing the circuit at the point gives me a very quiet signal with poor quality (compared to testing it where it enters the breadboard).
Have I made a mistake in the circuit (I can't see one) or is there something wrong with the diagram?
Thanks,
ADDED: I've also just noticed that connecting the sounder between the positive rail and the signal ground actually plays the audio input signal, and the three unused output pins of the op-amp (TL074 - it's 4 in one chip) give the audio signal.
I am constructing it on a breadboard at the moment, and I've got as far as the 10R resistor coming out of the first op-amp. I'm periodically testing the audio signal that comes out with a small piezoelectric sounder to check that I haven't made a mistake in the circuit. Testing the circuit at the point gives me a very quiet signal with poor quality (compared to testing it where it enters the breadboard).
Have I made a mistake in the circuit (I can't see one) or is there something wrong with the diagram?
Thanks,
ADDED: I've also just noticed that connecting the sounder between the positive rail and the signal ground actually plays the audio input signal, and the three unused output pins of the op-amp (TL074 - it's 4 in one chip) give the audio signal.
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