Issue link: https://digital.copcomm.com/i/3788
36 Post • October 2009 www.postmagazine.com like an educational documentary shor t film, usually under 40 minutes long. Sure, there are more IMAX theaters popping up and Hollywood has been trying to get on board, but until we get over the obstacles of filming in IMAX, I don't think you will see a tradi- tional Hollywood-type film shot in IMAX, fully. That will most likely change when we get to an all-digital version of it." The IMAX audio format is different from the standard 5.1 layout. "The current IMAX format is 6 channels laid out as left, center, right, left surround, right surround and over- head," says Teaney. "The single overhead speaker is located at the top of the IMAX screen directly above the center speaker. There is a seventh speaker that is a sub- woofer, but it is not a seventh channel.This is somewhat of an enigma because it is not a discreet LFE channel. Like any subwoofer, it derives its information from all the channels. All the channels are feeding the subwoofer at a cer tain frequency range, at 120Hz and below. Those of us who work this format have asked for an LFE channel because it would nice to mix specifically for the sub." Now, with the surround speakers, it's a level playing field, he says. "It is sonically pure, because you don't have a limited frequency range like you have with a standard film. Here, the surrounds are the same size as the front speakers behind the screen. Full range surround speakers make for some pretty in- teresting stuff that can happen behind your head. Now, combine that with the fact that IMAX theaters are almost always wider than they are longer, the result is that the sur- rounds feel like they are a lot closer to you. It's like the sound is right by your head." The IMAX surround sound format of- fers the experience of height with a single overhead channel. "The overhead is an in- teresting speaker because we use it spar- ingly," he says. "I mixed a film called Dol- phins, which is a great example of how most of the action is at the bottom third of the screen. So when the dolphin goes up to the surface to breath and breaks the sur- face, you hear that at the top of the screen. It's a magical moment in the film because of the overhead channel. Another good ex- ample is with the mix I did for Everest, which is the highest grossing IMAX film to date. We star ted the avalanche at the top of the screen in the overhead speaker. As the avalanche came down the screen, so did the sound. It comes down from the overhead, into the center, then spreads into the mains, and buries the camera and sweeps behind you into the surrounds. The cool thing is that the sound never changes with its full range of frequency and inten- sity. It's such an amazing physical force when it comes off the mains and into the surrounds.You really feel it." Grand Canyon Adventure: River at Risk was mixed at Burbank's Todd-AO on Stage 2 using the AMS Neve Digital Film Console. The Lexicon 480L was used for reverbs and the iZotope RX plug-in was used to help re- move the excessive noise created by the IMAX camera on the dialogue tracks and production sound. "We always do a quick knock-off print master and run over to the California Science Center to listen to it in an actual IMAX theater," says Teaney. "We take our notes there and then make changes based on what we heard there. "The IMAX format is an amazing sonic experience," says Teaney. "It's designed to allow the audio to be as large as the picture. We can do full pans from back to front and not have to compensate for any limitations because the surrounds are the same size as the mains and can reproduce anything the mains can. What makes it such an immersive experience is that the surrounds can put the audience in the middle of what they are see- ing. It's so much fun to work in, it's a sonic playground!" Todd-AO's Ken Teaney mixed the IMAX film Grand Canyon Adventure on an AMS Neve Digital Film Console. Surround Sound