The input section is where you'll set incoming signal levels and set whether Stardust 201's effects are in stereo or monophonic-al. Note that the effects routing is as it appears on the front panel - that is, chorus, then echo, then reverb.
Output Meter and Peak Level LED- You know the drill here - set the level so the needle mostly stays in the green. The red LED illuminates when signals are in the red. You're of course welcome to push signals into the red, it won't void your warranty.
Mono/Stereo toggle- Sets the output signal for mono or stereo operation. This only affects wet signals - incoming dry signals will not be altered, that is, stereo signals won't get mixed down to mono. Unlike an original Space Echo, which is mono only, Stardust 201's chorus, echo, and reverb effects can operate in stereo.
Input Volume- Sets the gain level to the effects. Cranking this guy into the red will distort the input in a raunchy, analog-correct fashion.