LR Baggs iMix Onboard - Manual (Page 8)

3. Mix control: The position of this knob will determine how much of each
pickup's signal will be present in the overall mix. When the knob is turned
completely counterclockwise, the output will be 100% Element; likewise, when
the knob is turned completely clockwise, the output will be 100% iBeam. For
most situations, the best position is 12:00.
4. Treble and bass controls: These controls adjust the level of high and low
frequency output.
5. Phase: This inverts the signal phase. If you are experiencing feedback, this is
the first tool that should be used. However, depending on your position in
relation to the
speaker(s ), pressing this button may have no effect or even make
the problem worse. Also, phase inversion is of little use if you are moving around
the stage. There is no way to predict beforehand whether or not you are in the
correct phase setting without using this button.
6. Stereo/mono switch (on underside of preamp): This controls whether the
output is summed to one mono channel or split into two signals. The stereo
position is toward the neck, mono is toward the tail block. The default setting is
mono, which mixes both pickup outputs into one signal, to be run down a
standard mono cable. Stereo mode requires the use of a standard stereo cable
or stereo Y cable; this mode puts the Element on the tip channel and the iBeam
on the ring channel. If you use a mono cable in stereo mode, only the Element
will be present.
In stereo mode, the volume, mix and phase controls are fully functional; only the
treble and bass sliders are defeated. Phase inversion will affect both channels,
and the mix knob will control the level of output for both pickups in their
respective channels. With the mix control at 12:00, both pickups will have equal
output; rotating it will decrease the level of one pickup until that channel is
completely silent, while slightly increasing the volume of the other pickup in its
channel. The master volume affects the levels of both channels equally.
This setting is useful for recording each pickup independently, creating separate
blends for two different sets of speakers (for example, the house speakers and
stage monitors), or applying different effects to each channel.