This is one of those pedals that has loads of mods for it.
I picked mine up 2nd hand and broken.
The pedal did light up but made no sound, when I opnened it up there was one thing glaringly obvious that the pedal had been electrically abused. The polarity protection diode was cracked in two and a little burn on the board. What wasn't visible was that the SIP opamp was dead.
Since SIP chips aren't readily available at the local electronics store, I decided to make a little mod board to wire in a high quality op amp(opa2134).
Once the pedal was working, I finally got to hear the infamous DS-1.
Not my cup of tea honestly. Very fizzy sound.
Next I did the All seeing eye mod. Not bad, the distortion improved a bit.
The pedal had too much gain for me so I went and added the Fat Mod.
Additionally to the fat mod I went and installed a couple of switches to get the pedal back to the stock gain and EQ setting. Overall the pedal is fairly flexible, but a little too gainy for me. Actually even the humble SD-1 has too much gain, I like a little break up when i hit hard, but clean when I play more sedately.
Thwe DS-1 is a modders delight, I'm sure there are a bunch of other things you could try, but I kinda ran out of room in the little box.