Op amp distortion pedal problem

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electrodarkness

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I'm developing a distortion pedal for my electric guitar, but the circuit behaves odd. If I connect my PC output to the pedal I can hear the distortion, the EQ change, but if I connect the guitar to the pedal input I can't hear anything ( even if I hook it up with another clean boost pedal, the output is too silent). Could this be of the wrong input impedance matching? Also the distortion is somewhat mild, the calculation and simulation gave more fuzzy result.
The schematic is attached. Any help would be appreciated.
 

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The input buffer misses a bias resistor but I guess it will work though.

Input and output buffer are effectively useless regarding TL074 properties, BS170 is adding a considerable noise amount, however.

Generally, you should check the DC voltage levels of stages to determine correct operation. Better trace an AC signal through the stages.
 

The output from a traditional guitar pick up is low impedance and low level ~ 10mV?
Click to expand...
Rather 50 to 100 mV if I remember right. "Can't hear anything" suggests a fundamental circuit wiring error.
 
Well the problem was with the filtering capacitor after the mos-fet. Now I've changed some stages on the effect pedal. I post the schematics if someone's interested.
 

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Out of curiosity, why did you use discrete input and output unity gain amps rather then using the 2 remaining OP-AMPs in the TL074 package?
 

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