The Boss DS-1 is a common and in many ways classic guitar effects pedal, but surprisingly enough, it just doesn’t sound very good. Because of this, you’re likely to find used DS-1s for cheap. Instructable author James Haskin wrote up a step-by-step on how to implement the well-known Keeley Seeing Eye and Ultra mods to enhance the lackluster sound -

Every guitarist at some point has at least tried Boss’s DS-1 distortion pedal. Most People are immediately disappointed. This over hyped pedal sounds really thin with no punch. Sales people at guitar center will say something like its a “great beginner distortion pedal”. Its been my experience that most of the people that work at guitar center are useless. So, always research and get information from multiple sources.

The DS-1 is actually used by many artists including Joe Satriani, Kurt Cobain, John Petrucci, and Steve Vai to name a few, BUT most of the big artists don’t use the stock one. Why? Cuz it sucks!

The good news is this pedal is simple enough to modify!! In this instructable I will show you step by step, with lots of pictures, how to perform Robert Keeley’s DS-ULTRA Mod.

While not the simplest of mods, the process involves replacing 3 resistors, 4 caps, and an LED – the resulting improvements seem quite worthwhile for pursuers of “ultimate tone”. Check out the instructable for all the deets.