Can enyone help me identify this DIY stompbox?

(make that "anyone")

I found this in a guitar shop here in Taipei. I'd be EXTREMELY surprised if a local made this, but stranger things have happened.

I've attached some photos below...

There are two main amplifying components on it, a little 8-pin chip and a transistor.

The chip is marked:

OP275

G 0338

03711

And the transistor is marked:

C550B

PH47

There are three controls on it, labelled in the photo.

There are two toggle switches. The one on the side is a 3-way, with capacitors in 2 of the positions. It works as a sort of tone filter I guess. At the back is a two-way switch, which appears to work as a kind of turbo overdrive.

I guess this pedal sounds a bit like a tube screamer or something, but don't let that influence your guesses.

Any ideas?

It'd be great if it turned out one of you made it, hehe. It's pretty well made, btw.

Thanks.

OP275 used in Boss SD-1 mods: http://www.geocities.com/overdrivespider/SD1/opamps.htm

Interesting thing about that "Gain" pot - it looks as if it's stereo, right?

Correct (and good eyesight). It is stereo.

Interesting link. Thanks.

Anyone else? This PCB looks like it may have been bought, or made from a downloaded image, leading me to suspect that there's a project listed somewhere on the net for this pedal, possibly with a different transistor/op-amp combination (P.S. I noticed that the transistor has been swapped out after the fact).

Thanks again.