TREBLE: Controls the higher frequencies. clockwise for more; counter-clockwise for less. Acts like a ‘mixer' control between the treble side and the middle/bass side.
MASTER: Controls the overall volume of the pedal. Clockwise for more; counter-clockwise for less. For the best response out of your DLS, you should set the Master volume so that the sound with the DLS engaged is a bit louder than your bypassed sound.
MIDDLE: Controls the mid frequencies. Clockwise for more; counter-clockwise for less. This frequency gives energy to the guitar’s sound.
BASS: Controls the lower frequencies. Clockwise for more bass; counter-clockwise for less. Don't feel like you're doing something wrong if you find yourself wanting to run the Bass control at a very low setting as there is plenty of low-end on tap.
PRE-AMP: Determines how much gain or overdrive. Clockwise for more; counter-clockwise for less. The lower you have the Pre-Amp knob, the higher you'll want to have the Master control, and the higher you'll be able to get away with setting the Bass knob.
INTERNAL CONTROLS
PRESENCE TRIMPOT: There is a trimpot (accessible by removing the bottom plate) that allows you to fine-tune the amount of presence or high treble frequencies that the pedal produces. It is factory set to provide the best tone in most circumstances.
SL/SB MODE SWITCH: Two distinct voicings: "Super Lead" and "Super Bass" are switchable via an internal slider switch. The mode switch can be accessed by removing the four screws of the bottom plate. It is located up at the top left corner of the pedal.
You can power your DLS with any quality power supply designed for use with effects pedals. The output should be a negative tip DC from 9 to 18 volts. If you want more volume, headroom, and percussive attack, try running an 18-volt power supply. A nine-volt power supply will have a slightly softer sound that saturates more easily—it's sort of like the difference between a 50 watt and 100 watt amp!