MXR Pedal FX Booster is a pedal featuring a knob adjustment from 0 to +20 dB to enhance cleanly without coloration.

True bypass, connect a cable from your guitar to the input jack of the line / boost controller and run another cable from the output jack of the boost / line controller to your amplifier.

Start with the Boost knob at 0dB. Turn the knob clockwise to increase the boost level, up to +20dB.