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!

The Dirty Little Secret (DLS) Red was designed to be the secret weapon in your tone arsenal. Want to get cranked amp tones at bedroom rocker levels? Playing gigs but have to use whatever amp is provided as the back-line? Like your clean amp sound but don't care for its overdrive channel? Love your fuzz pedal but it needs to be plugged into a cranked amp to sound good? Enter the Dirty Little Secret!

Designed to bring you the sound and response of a classic Marshall amplifier, the DLS Red is designed to be a "foundation" pedal—it is your "always on" pedal that forms the core of your guitar sound which you can enhance and embellish by adding boosters, fuzzes, filters, and other overdrives in front of it—just like you would in front of a real amp. And the reason you can leave it always-on is that you can get a great clean sound just by rolling your guitar's volume knob back! That's the way the old school Marshall players did things!