Is it possible to route a dry audio signal to one of the outputs, so for instance the fx processed signal is on mix 1 and the dry signal is on mix 2?
Yes this is possible, but would need more detail to be any more explicit. Don’t confuse the mixes with the outputs - they are separate!
Okay, say I want an audio track with a guitar in Cubase 7.5, with Amplitube 3 as an insert effect.
How can I route the signal in the mixer so that the processed signal (through Amplitube 3) is delivered to Mix 1 and the physical main outputs, and the dry signal is delivered to Mix 2 and output 3/4 (if I remember the manual correctly)?
Maybe easiest would be to send the guitar input into a track 1 routed to mix 2 (out 3/4), with a send to a track 2 where will have the Amplitude is inserted, and that track routed to mix 1 (out 1/2).