Theres 3 knobs for tone, level, and distortion. Boss provides a battery for it, but you can also plug in a standard 9V adapter.
The simple setup makes it easy to use. With only three knobs, there's not a whole lot to fuss around with, but there is still enough room to vary the sound a bit. The controls all respond how you would expect them to.
The pain with this pedal is, if you're using a battery, like many pedals you must unplug the input or the battery will drain.
I like this pedal quite a bit. It's got a crunchy, "fizzy" distortion that I enjoy. The tone knob will take some adjusting to find the sound you want. It seems to start off a bit muddy on the low side and gets a bit too bright on the high side. But I like to vary the fullness of the sound and the tone works well for that.
The distortion will provide some nice crunch even on its lowest setting, and add the "fizz" as you turn it up. Level works well to help dial in the sound.
It's probably not for everyone, but it's perfect for a basic distortion. It also seems to work well with fuzz boxes and other pedals.
Okay, the DS-1 sells new for $40. At that price, you can pretty much afford to hate it. For a basic distortion pedal, I think there is very good sound here which makes it an incredible deal. I've heard more expensive pedals that I didn't like so much. Anyone who is looking for a distortion should give this one a shot. I bought this pedal just to try it. It was much better than what I was expecting.
And like most Boss pedals, it's very sturdy, so it'll probably last a lifetime.