One Control Anodized Brown IC

[stevenrb718]

Anybody happen to know what IC the One Control Anodized Brown distortion pedal uses? I'm getting a high squeal after 12 o'clock on the gain and the IC is scratched out.

[g1]

There is an unverified schematic in the wayback machine that shows TL072.

[stevenrb718]

I wonder how different the ABD 4K is from the ABD. Looks like some of the components are the same, but the 4K has an additional voltage regulator and transistor that the ABD doesn't. I would think they would have used the same IC from the previous model but I'm not sure. I would have thought it would be something with a higher gain than a 072.

[Helmholtz]

I would have thought it would be something with a higher gain than a 072.

So you think a gain of 100000 up to one million might not be sufficient?

[stevenrb718]

So you think a gain of one million (= 120dB) might not be sufficient?

Haha, no. I mean a bit more niche I guess. Why bother scratching it out if it's a 072. I thought maybe it could be a 5532, 358, or 741. I dunno. The way the pedal is designed, there's no room to put a socket in and swap ICs, unless I ran jumpers, so I just want to be right before connecting the PITA back up.

[g1]

They scratch the number out so people think there is something special inside. They know if they leave the lettering on it, people will have a similar reaction as you did, expecting there would be something more exotic in there.
I suppose it would also prevent some with very limited electronics knowledge from cloning it.
I don't know how the person that drew up that schematic would know it was exactly a TL072, but rather something matching the pinout and general specs. (unless 4K version not scratched out)

[stevenrb718]

They scratch the number out so people think there is something special inside. They know if they leave the lettering on it, people will have a similar reaction as you did, expecting there would be something more exotic in there.
I suppose it would also prevent some with very limited electronics knowledge from cloning it.
I don't know how the person that drew up that schematic would know it was exactly a TL072, but rather something matching the pinout and general specs. (unless 4K version not scratched out)

I imagine it was an educated guess. I emailed OneControl and they said they don't give out information on the chips in their products, so I assume it's scratched out on the 4K also. I feel like I can almost make out lettering, but I really can't. It wouldn't be much of a problem if I could set the pedal up for testing ICs, but the layout is so funky. I'll try and trace out the board and compare it with the schematic just to make sure the pinout is correct. Then I guess I'll drop in a TL072 and see what happens.

[Mick Bailey]

If the pedal works OK up to the point where the problem starts, I wouldn't automatically suspect the IC.

[stevenrb718]

If the pedal works OK up to the point where the problem starts, I wouldn't automatically suspect the IC.

Not a whole lot to the pedal; I'm not sure what else could be causing the oscillation. I had a Marshall Guv'nor 2 with the same problem once that was the IC. I guess I could try dropping the TL072 from the ABD into another pedal that uses it and see what happens, but the chances of a similar issue occurring probably isn't good.