Source Audio ZIO User Manual page 10

gain to your liking. The trim pot functions like a normal potentiometer: turn clockwise for more gain,
counterclockwise for less gain.
Please note: the GRIT circuit is very interactive with the input signal of your bass or guitar. Thus, you
may need to adjust the trim pot accordingly, depending on the output of your pickups and your gain
preferences.
Below is a frequency spectrum comparison of the GRIT control OFF and the GRIT control ON. All
other controls are set to flat.
GRIT OFF (Flat):
GRIT ON:
As you can see, there is not much of a tonal change when GRIT is enabled and all other controls are
enabled, except for a minor treble fall-off beginning around 1100Hz.
SA272 ZIO Analog Bass Preamp + D.I. User Guide 10