When listening to progressive rock, a progasm can be reached when you go very deep into the music and that you let it take control over you. This instrumental trance can be called a progasm, especially when you actually wet your pants doing it. One of the main particularities of the progasm is that it is often accompanied by frenetic air-guitar playing, as well as air-keyboard, air-drum, air-bass, air-flute or even air-accordion.
Why is the progasm only related to ''progressive music'' ?
Progressive music often contains extended solos and very complex interplay between many kinds of instruments, some of them being pretty unusual. A song which is constituted of several tempo changes, unusual time signatures, incredibly fast arpeggios, absolutely original synth sounds, dissonant chords, a church organ interlude and out-of-this-world vocal harmonies has more chance to simply blow your mind than a standard 3-minute pop song. Real progheads can actually get sexually excited when hearing a fully accomplished prog song.
OMFG dude. Did you listen to this overextended keyboard solo by Keith Emerson? This is just fucking awesome: I had a progasm!!!