This is probably the one of the best kept secrets on the planet at $40 USD. This pedal is a sleeper and a steal. New, it is half of what a used TS9 sells for on eBay. What’s really amazing is how great this pedal sounds with my $20 Mod. So for $60 and little time you get a pedal that blows away the competition. No hype, this Mod is THAT Good! Even I am shocked at how well this mod turned out. Stock the SD-1 delivers warm fat tones. The stock SD-1 from the factory sounds rather bland and not very transparent. The PCB is almost exactly the same as a Tube Screamer.
The stock SD-1 also comes with the famed JRC4558D opamp chip. You can change the character of the pedal buy swapping out different chips which I now sell above. This mod will make you want to throw away your Tube Screamer. Well, maybe not, but this mod transforms this already good sounding pedal into absolutely one of the best Overdrive pedals sold anywhere at any price! With this mod I tried Carbon Composition, Carbon Film, Metal Film, Tantalum, Rectifier Diodes, LEDs, Germanium Diodes, etc. just to see what affect each one would have on the SD-1’s tone. The Mods below are a result of that research and experimentation.
IMPORTANT — Boss has started using surface-mount components on some of their new pedals. I’ve created a page to help you determine if your pedal is moddable. Read about it here.