Science: Sound on Cellophane

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A new sound-recording machine which may upset the recording industry was in production last week in Manhattan. A compact affair not much bigger than a portable radio, it makes records on Cellophane tape. They are first class as to tone, and in durability, ease of production and cheapness they beat any records previously produced.

The machine is a record addict's dream. It can be plugged into a microphone, radio or telephone for recording; then a flip of a switch sets the machine to play the record back. Its Cellophane tape permits eight hours of recording or playing without changing. Its sapphire needle does not have to be changed, never scratches the record. The high-fidelity cellophane record, which costs only 50¢ per hour's recording to make, emits almost no surface noise, can be played thousands of times. The inventor plans to turn out a smaller home model of the machine for $50.

He is a longtime cinema sound man named Jay Fonda. He got his idea from the movie sound track. He thought that a sound record on film, using a needle instead of the strong light by which a movie track is translated into sound, might have many advantages over records made of wax disks or cylinders. But how to press a sound track on film with a needle, without cutting through the film? Fonda finally solved that problem with a "yieldable bed" of felt under the film, which would permit the needle to emboss a groove in the film without cutting through it.

Feet and Hours. For the film, Fonda uses Cellophane twice the thickness of cigaret wrappings. The recording tape, a little over an inch wide, is an endless loop 350 ft. long; once around is eight minutes and in eight hours of recording the needle cuts 60 parallel grooves in the tape. Cellophane records are less bulky and more permanent than recordings on magnetized wire (TIME, May 17); the wire is subject to magnetic interference. Cellophane recording also seems likely to be a good deal cheaper for some time to come than light-wave recording (as in movie sound tracks), even if that process were reduced to domestic scale.

Although the Fonda recorder obviously has a great variety of possibilities, wartime material shortages have so far limited its use to a few important jobs. Chief use: as a monitor in airport control towers.

In the home, the recorder's anticipated uses range from catching the baby's early cooing to reproducing broadcast music. Cellophane records, unlike disks, cannot be produced in quantity by molding from a master record, but Fonda expects no great difficulty in finding ways to achieve mass production. Neither do the young manufacturers behind the making of the Fonda recorder, Jefferson-Travis Radio Manufacturing Corp.