Dolby A-type noise reduction, the original professional Dolby system introduced in
1965, is used on Dolby movie soundtracks. Dolby's first technology was Dolby
A-type noise reduction, introduced in 1965. It was designed for use by professional
recording studios to make quiet master tape recordings. In the early to mid 1970's

its use was extended to film recording studios and motion picture release prints in order to make
films sound better.

The prototype for the

IMAX

system is exhibited at EXPO '67 in Montreal, Canada, where multi-

screen films were the hit of the fair. A small group of Canadian filmmakers/entrepreneurs (Graeme
Ferguson, Roman Kroitor and Robert Kerr), who had made some of those popular films, decided to
design a new system using a single, powerful projector, rather than the cumbersome multiple
projectors used at the time. The result: the IMAX motion picture projection system. IMAX
technology promiered at the Fuji Pavilion, EXPO '70 in Osaka, Japan. The first permanent IMAX
projection system was installed at Ontario Place's Cinesphere in Toronto in 1971.
IMAX Dome (OMNIMAX) debuted at the Reuben H. Fleet Space Theatre in San
Diego in 1973. The theaters tauted images of unsurpassed size, clarity and impact,
enhanced by a specially-designed six-channel, multi-speaker sound system, projected onto giant
rectangular screens, up to eight stories high. The IMAX image is ten times larger than a
conventional 35mm frame and three times bigger than a standard 70mm frame. The key to the
projectors is the "Rolling Loop" film movement devolped by Australian Ron Jones. The projector
advances the film horizontally in a smooth, wave-like motion. The sound system is generally run by
10,000 to 20,000 watts of amplification, with most theaters possessing six-track stereo
surround-sound and a 3,200 watt 3,000lb subwoofer. The sound is on 35mm magnetic 'dubber' film
(today this is back up for the 3 compact discs that are used). Most shows are run at 85db.