A few builds

tcpoint

Well-known member
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Really nice pedal and super simple.

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Really nice compressor - not a big Cornish fan but really like this (OC-1) and the SS3.


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Dan Coggins nailed this. The OTC-201 is awesome and easy to use.

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Another really nice pedal. Very versatile. Does the classic rock and high Gain stuff. Cleans up nice. Would be good for blues, as well.

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Another really nice pedal. A little noisy but I'm working on it. Stole the artwork. I'm always game to stealing artwork.

Still working on matching knobs. Sorry, but was too lazy to open up the pedals for all the gutshots.
 
The OPA1678 is quickly becoming my goto replacement for the OPA2134. Less than a buck and better specs. It only comes in SMD packages but adapters are cheap. I used an OPA1632 for the 805. I didn't have an MC33178 and happened to have an OPA1632 on hand. I have several recommendations for OPA2134 alternatives, but for a guitar pedal, I don't think you can go wrong with the OPA1678, especially for the price.
 
The OPA1678 is quickly becoming my goto replacement for the OPA2134. Less than a buck and better specs. It only comes in SMD packages but adapters are cheap. I used an OPA1632 for the 805. I didn't have an MC33178 and happened to have an OPA1632 on hand. I have several recommendations for OPA2134 alternatives, but for a guitar pedal, I don't think you can go wrong with the OPA1678, especially for the price.

i on the other hand have a bunch of opa2134 left over from chip rolling... does the flavor of op amp in this circuit really matter aside from the noise floor? or can i even get away with with something like an lm833 or ne5532 without too much noise?
 
I bet I couldn't tell the difference between the ne5532 and the OPA1632 and the MC33178. I haven't rolled any opamps in it. It's dead quiet even with the gain maxxed. The opamps really seem to make a difference with the compressors. I made a Dist+ and put a good opamp in it - it sounded like crap - it really needs a LM741.
 
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well i know they all have different slew rates and... idle current requirements? something like that anyway. i have a couple of 805 pcbs im gonna build soon, ill socket the op amps and report back.
 
i on the other hand have a bunch of opa2134 left over from chip rolling... does the flavor of op amp in this circuit really matter aside from the noise floor? or can i even get away with with something like an lm833 or ne5532 without too much noise?

Depends on the pedal. The pedals that drive the opamps into saturation (Angry Andy, Muroidea, Parenthesis, etc.) will sound different with different opamps. The ones that don't allow the opamps to saturate (TS clones, Integral, etc.) will all sound pretty much the same. After that, it's down to noise floor.
 
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