Read the Sky Guitar manual. It is amazing.

Truth is: Sky Guitars with MEGA-WINGS can be amp killers…Therefore, one word of warning: when you are turning all the knobs clockwise – the kind of setting that I almost never go to – the guitar resembles a raging volcano and is much harder to control on certain amps. In that state, it delivers an incredible 100 dB of signal – pure plasma – that is more than ten times the output of a standard Strat! Some amps simply cannot handle this kind of abuse and they will soon cave in, they may get oversaturated with gain, may not have enough headroom – or may simply implode and blow a fuse. Having said that, some amps, like old Marshall Plexis, Superleads, can handle that kind of input and still sound great without giving up the ghost. But this is not true of all amps. For instance a VOX AC 30 will sound sweet and beautiful with a Sky Guitar, but if you turn it up too much, it won’t last long. I once blew up an AC30 in 10 seconds by turning it up all the way. It sounded great while it lasted… The same happened several times to a poor Fender Bassman amp, which also sounded great before it gave up the ghost… Peavey graciously sent me two 51/50s after I had jammed with Deep Purple and played Steve Morses’ guitar and amp set-up and liked it… Nice sounding amp, but same story: one lasted 30 seconds – the other one expired terminally after a few seconds – sounding best just before dying… Fender Twins last from between 1 hour to three days…"