The Boss DS1 Distortion Effects Pedal delivers added sustain and distortion types that range from very soft to very hard.
With its level control, you can set the DS1 to match your volume level, or to get that boost when you go into a lead. Other controls are tone and Distortion (affects the amount of distortion).
The DS1 provides a harder distortion effect for guitar and keyboard sounds. Instead of toneless, fuzzy distortion, the DS1 faithfully reproduces all the subtle nuances of your playing dynamics, from whisper-quiet to screaming loud. The onboard TONE control allows you to tailor the overall sound to your liking.