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THE PATHE VOX 9.5mm SOUND PROJECTOR
Mike Trickett

The VOX started is life in 1937 as a silent projector with the simple model designation of
Model “S” (for silent?). This machine was basically the VOX without any of the sound parts
included. Within a year, Pathe was offering to upgrade the “S” to sound and was offering the
complete unit as a Pathe VOX 9.5mm sound on film projector.
As with most Pathè
equipment, the VOX was
unconventional. The
machine had an off-set film
path, necessary to allow the
gate and lens assembly to
lift up to thread or clean the
gate. The lighting source
was a 15volt 200watt lamp
w i t h a s t r a n g e o f f - s e t
filament (see illustration),
which was mounted base
up. The reason for this
arrangement became
evident when the sound
system was examined. The
projection lamp was also
utilized as an exciter lamp,
the exciter lens being
mounted directly under the lamp house, picking up light from the projection lamp and
focusing it on the sound track.
Exciter lens
Rotary shutter (volume control)
The sound system was yet another
strange system. The light slit from lamp
house, after passing through the sound
track on the film was reflected by a mirror
into a type of chute which fed into the
photocell, which was mounted in the
amplifier compartment at the rear of the
machine. There is no volume control in
the conventional sense on the machine,
instead there is a rotary shutter
incorporated into the chute which can
allow more of less of the reflected sound
track to get to the PE Cell. (A system that
Pathè again used on
their 17.5mm Home Talkie).
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