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Perspecta Sound by Mike Trickett

place inside the Perspecta integrator unit. Of course three
amplifiers and speaker systems were required. The beauty
of the system was in its flexibility; likes today's Dolby
Stereo sound tracks, complete compatibiJity with older
mono sound heads was maintained when running a
Perspecta film.

In Australia, it was mainly the Metro Cinemas that were
equipped with Perspecta three channel equipment.

The Perspecta multi-directional sound system was designed
in the USA by Robert Fine of Fine Sound Inc.; the equip-
In an effort to combat the inroads that the growing popu- ment was manufactured in New York by the Fairchild Re-
larity of the new stay-at-home entertainment medium of cording Equipment Co. As would be expected for that era,
television was having on (USA) audiences of the day, the it was all-valve equipment.
1950s saw many innovations in the professional cinema
industry. Cinerama allld CinemaScope both with multi Although frequently referred to as stereo, Perspecta is not
channel sound, Vista Vision, 30 and Perspecta Sound were true stereo. The Perspecta system provided a system of
but a few. electronically directing the mono sound track to any of
three speaker systems placed behind the screen in a left-
Industry publications ( I) of the time suggest that many centre-right set up. The sound could be sent to one, two or
exhibitors as well as their technical staff treated these in- all three speakers simultaneously. Despite the fact that the
novations with indifference and in some cases put up a sound was directional, it was still only a single mono sound
solid wall of resistance to change; such was the fate of track. Perspecta 'sown advertising generally described their
Perspecta Sound. system as Multi-Directional Sound.

introduced well before the popularity of the home stereo, Comparing a well-mixed Perspecta sound h·ack presenta-
this highly effective 3 channel directional sound system tion with today's Dolby stereo, the first thing that becomes
was installed in only a handful of cinemas; even when apparent is that the sound is capable of following the per-
installed, it was often poorly adjusted, or even worse, not formers on the screen. When an actor on screen right
turned on. speaks, tl1e sound comes from screen right; if another per-
son speaks from screen left, the voice comes from screen
The first feature to be released with Perspecta Sound was left. This gives a true directional sound effect. This is not
MOM's Knights of the Round Table staring Robert Taylor the case with Dolby Stereo suLTound, which mainly con-
and Ava Gardner in 1953. Prior to this, Metro had re- fines the dialogue to the centre channel, with left-right
leased some cartoons and possibly other short subjects in stereo music and effects. There are technical reasons why
Perspecta Sound (2). Many of the mid to late 1950s re- this is so, but that's another story.
leases from MOM, Warner Bros. and Paramount (3) were
released with Perspecta Sound sound h·acks. Its demise The secret of Perspecta lies in its use of three very low
came around 1960, mainly due to its poor promotion and fi·equency tones to control the directional switching of the
lack of interest by exhibitors. sound. These tones are mixed in at the time of recording
the sound track, and are recorded along with the usual
Many films of the time were released in different ver- music, dialogue and sound effects onto the normal mono
sions. [twas common for big name films to be released in optical sound track.
both a magnetic stereo and an optical sound version (even
Cinema Scope and non-'Scope versions). Many of the op- When in operation, if the Perspecta decoder unit detects
tical sound versions were released with Perspecta Sound the presence of one or more of these low frequency tones,
encoding. it will automatically switch into Perspecta mode. From
there on, the presence or otherwise, of the individual low
Perspecta Sound gave even the smaller cinemas a means frequency tones will determine which speakers are turned
of providing pah·ons with an up to date stereo sound pres- on or off. Although only the one sound track is present on
entation at a relatively low cost, (in 1954 the system sold the film. these tones will determine whether it will be
in the US for $990.00) while maintaining full compatibili switched to the left, centre or right speaker(s) or any com-
ty with existing mono optical sound tracks. Unlike mag- bination of them.
netic sound, no changes to the projection equipment was
necessary (although the correct projector speed of24 frames The Perspecta decoder incorporates a high-pass filter cir-
per second was essential), all decoding and switching took cuit, which eliminates these low frequency tones from the

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