From the DOD Looking Glass Manual:
- LEVEL - Sets the output level of the effect. It is recommended that you turn this down when switching to high gain mode to avoid any large jumps in volume.
- GAIN - Controls how easily the pedal is pushed into overdrive. Because the Looking Glass rewards dynamic playing, most settings can produce a clean sound when picking lightly. The maximum level of overdrive increases as this knob is turned up.
- BASS CUT/TREBLE - The BASS CUT knob adjusts the amount of low end content in the incoming signal (before the overdrive). It is recommended that you start by setting this control at noon and adjusting upwards or downwards to thicken or clear up the overdrive to taste. Hint: Set at maximum, this control produces a very raw sound.
The TREBLE knob adjusts the brightness of the pedal’s overdriven sound. Hint: You may want to move this control to roughly line up with the Bass Cut control for a balanced sound The concentric control design makes this easy to do on the fly. Or, for less neutral sounds, set the two indicators differently from one another to create the drive sound that works best for you.
- INPUT FILTER - This is a variable filter that adjusts the tone of the input signal. To help match with brighter guitars and reduce the prominence of spikey pick attacks, turn this control more to the left. For a brighter sound with more prominent attack, turn this control all the way up. This control also will adjust the midrange content of the signal so that midrange becomes more prominent as the knob is turned more to the left.
- HIGH/LOW - The Looking Glass offers two different overdrive modes.
The Low mode is used for clean tone shaping, light compression, and lower gain overdrive.
The High mode pickups up roughly where the Low mode leaves off by boosting the pedal and allows you to dial in Low to High gain overdrive sounds that remain highly touch sensitive all the way through the range. Note: It is recommended that you turn the Level down when switching modes to avoid loud jumps in volume and re-biasing noise as the pedal adjusts itself to the new gain setting.