Hi guys, I have an Integral Pre (TC Integrated Preamp) that I built a while ago, the only problem I have with it is I get some op-amp clipping with my loudest guitar when I wang on the strings hard (which is most of the time). I know the build is fine as my original TC integrated preamp, as well as my veroboard clone from back before the pedal was hyped, both exhibit the exact same behavior, and otherwise sound the same.
From what I understand the pedal is just a fixed gain op amp amplification stage and a two-band shelving EQ, with some additional fluff around the input for anti-pop when plugging/unplugging. I was hoping to reduce the op-amp gain slightly as I tend to have plenty of range left on the volume knob to make up for any loss, However it doesn’t appear to be a typical inverting op amp stage.
I’ve done some googling and the closest I can find to what the schematic looks like would be an integrator op amp (maybe makes sense based on the original pedal’s name?) but it doesn’t look like integrator op amp circuit is meant for audio.
Below is the schematic off the build sheet:
Does anyone know how I would reduce the op amp gain of this circuit?
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Also as a side note, I use this pedal as a boost to tighten the guitar sound into a high-gain amp for metal, which means I always have the bass turned quite low. The sweet spot tends to be quite small, between zero (very tight) and about 9:00. Stock bass pot is c50k, I replaced for a50k and this greatly extends the sweet spot, up to about noon. I tried a linear pot first, but very little difference. Would not recommend this if you ever boost the bass, however.
From what I understand the pedal is just a fixed gain op amp amplification stage and a two-band shelving EQ, with some additional fluff around the input for anti-pop when plugging/unplugging. I was hoping to reduce the op-amp gain slightly as I tend to have plenty of range left on the volume knob to make up for any loss, However it doesn’t appear to be a typical inverting op amp stage.
I’ve done some googling and the closest I can find to what the schematic looks like would be an integrator op amp (maybe makes sense based on the original pedal’s name?) but it doesn’t look like integrator op amp circuit is meant for audio.
Below is the schematic off the build sheet:
![integral preamp tc pre schematic.png integral preamp tc pre schematic.png](https://forum.pedalpcb.com/data/attachments/25/25534-a5f8609c2a339cee9f2176d063e2e2d9.jpg)
Does anyone know how I would reduce the op amp gain of this circuit?
------------------
Also as a side note, I use this pedal as a boost to tighten the guitar sound into a high-gain amp for metal, which means I always have the bass turned quite low. The sweet spot tends to be quite small, between zero (very tight) and about 9:00. Stock bass pot is c50k, I replaced for a50k and this greatly extends the sweet spot, up to about noon. I tried a linear pot first, but very little difference. Would not recommend this if you ever boost the bass, however.