DOD FX 102 Mystic Blues Overdrive Manual page 4

OPERATION OF THE FX102
The FX102 is an overdrive designed to work with or without
an already distorted amp. The FX102 gives your guitar that
"squishy" tube sound that other distortion pedals try to get.
From blues to just good old rock and roll, the FX102 can
change your guitar unlike anything else.
When setting up the effect, use the LEVEL control to match
the level of the distortion effect with the level of the original
input signal. The control should be set so that there is a
slight increase in level when the effect is switched into the
signal path. When using the FX102 in conjunction with a
distorted amplifier use it to control how hard your signal
"hits" the front of the amp or distorts it. The more it's turned
up the more the amp will distort.