2010 - Boss SD-1

This one came to me nice n' cheap. I bought it at a 2nd hand dealer in the city. $65 and practically brand new.
What do you do with cheap pedals? Mod them of course!

I'd read that this is basically a tube screamer with some parts changes.

Stock this pedal is pretty decent sounding, a moderate overdrive on full and a nice clean boost on minimum.
Unfortunately the filter caps on the input remove a lot of bottom end. So rather than add some punch, it cuts some of the guts out of it.

The first thing I did was to do the SD808 mod and turn it into a tube screamer.
Basically it's just changing one cap, removing another as well as a diode in the clipping stage.
What this does is make the clipping asymmetrical and alter the tone control.
To my ears and playing style, it wasn't much of an improvement. It still lacked the bottom end.

The next mod I did was the bass mod.
This is done by simply bridging two components, a capacitor and a resistor.
It was three weeks before I got around to testing it out, but when I did, the pedal was a whole new beast.
The gain still isn't much really, but that's OK I like it like that. The bottom end is nice and big, though a little muddy as there's a slight octave effect on some notes. But for the tone I'm after, this is almost perfect.

Placed in the FX loop of the Delta Blues, the pedal is responsive to dynamics and has the added bonus of acting as a master volume, though the extra gain from the preamp means that the pedal never completely cleans up.

I may end up doing some further mods to the clipping section and maybe change out the opamp for something else. But for now I'm pretty happy with this cheap pedal that cost about $1 and 15 minutes of my time to get close to what I want out of an overdrive.

Not too smooth, and just a little raspy.