More info on the sound, this time from IMAX.com:
"A surprisingly large part of the IMAX experience is the sound. That’s what makes an IMAX movie visceral. You don’t just see an IMAX film, you feel it in your bones.
"One reason is the sheer power of the custom, patented speaker system in an IMAX theatre. Another is the wider frequency response – which means higher highs and lows so low they’re as much vibrations as sounds.
"It’s also important to understand that what makes great sound so elusive is the fact that sound is altered by the listening environment and the medium used to deliver it. Simply stated, sound is affected by the room in which the listener sits as well as the quality of the source of the sound. IMAX has patents on theatre geometry that can control these variables - the shape, angles and dimensions are specific to IMAX. The theatre architecture has been customized and enhanced– with better soundproofing and more effective placement of the speakers. This allows us to create an optimum listening environment and deliver a result so precise that you can hear a pin drop from across the room – and know exactly where it fell.
"Finally, in an IMAX film, the soundtrack itself has been enhanced. Because of our proprietary Digital Re-mastering process, the sound of the original movie was re-mixed in post-production to recapture its full dynamic range, tweaked to make it brighter, crisper – and more exhilarating or scarier, depending on the context. This takes full advantage of the unique, responsive sound system in an IMAX theatre."