The panel on the right side is an input/output section for setting and
monitoring gain going in and coming out of Spectron.
Setting Gain:
You can adjust the input or output gain by sliding the faders with the mouse, either by clicking and dragging or clicking and using the wheel of a wheel mouse. As you change the faders, a display box will indicate the amount of gain being applied to the incoming (or outgoing) signal.
You can also use hotkeys to adjust the level in small increments. Learn more
about the hotkeys here...
Adjusting Left and Right Channels Independently
By default, the left and right gains are linked so moving one moves the other. You can adjust left and right gain independently by clicking on the "lock" icon. You can offset the two channels and then "relock" them, so that later adjustments move both channels by the same amount.
Faders will remember their offset even if they are temporarily turned up or
down all the way, so that when you bring the faders back to the middle the
offset will be preserved.
Double-click Resets
If the left and right faders are locked, double clicking on either fader will reset both of them to 0 dB.
If the left and right faders are unlocked and set at different levels, double clicking a specific fader will reset it to 0 dB.
If the left and right faders are locked but had been previously been set to
different levels, double clicking on a fader will reset it to match the level of
the other fader. Another double click will reset both faders to 0 dB.
More Information
Right-clicking (under OS X you can also ctrl-click) on the level meters provides an options screen for the level meters. You can learn about the level meters here...