Thnx again Marco for your reply.

Maybe because i've used eclipse  for a long time, maybe because i've used it just for delay, reverb and psychotic effects, the gap between my foot-tap and the availability  of the algorithm never frustrate me so much. Of course, it's a problem but at least i can use my time factor in a very easy and thoughtless approach. 

Anyway, your suggestion is the Aux Switch… never used it. Is it an external switch to change the preset up in one tap, right? Maybe it's the only way, but it's external… great frustration again, my back give praise.

Thank you, buona musica!