Movie Makers (Jan-Dec 1952)

203 FIG. 3: With only two sprockets, driven by worm gears for constant speed in film movement, Movie-Sound 8 is easy projector to thread. FIG. 4: Compact control panel offers complete audio facilities for all recording, playback needs. Center switch also controls the motor. are next to the sound stripe, as they are in the case of 8mm. film now being striped by Reeves Soundcraft, the distortion caused by the sprocket holes is transferred to the sound track as flutter or sprocket hole modulation. This is caused by the sound track moving slightly in and out of contact with the magnetic record and playback heads. It was necessary, therefore, to develop a new and patented film movement, which we called the RotoMagnetic Stabilizer (see Fig. 2). FILM SCANNED FLAT This Roto-Magnetic Stabilizer uses two rollers to hold the film tightly. Thus, the moving film can pass over the record and playback heads in a flat plane, eliminating objectionable sprocket hole modulation. The stabilizer also makes use of a sound drum which is slightly tapered, so that the film has a tendency to run to the outside edge of the drum at all times. This provides most of the edgeguiding necessary to keep the narrow sound stripe in the best contact position with the record and playback heads. The machine as a whole contains only two sprockets and is extremely simple to thread (see Fig. 3). The loop is automatically formed to size. The feed and takeup sprockets are driven by a worm gear which is connected to the motor by means of a special rubber belt. This is the type of mechanism employed for most high class sound on film recorders and gives a very direct drive from the motor to the sprockets. By using it, a constant sprocket speed is attained and the projector mechanism is made to operate more quietly. This is desirable, of course, because in a majority of cases the user will want to record with the microphone not too distant from the projector. RECORDING PROCEDURES To record and play back on the Movie-Sound 8 projector is extremely simple (see Fig. 4) . In order to record, you first thread the projector with a length of magnetically-striped 8mm. film. The control switch is then turned to either the P.A. position or the Rehearse position, and the operator speaks into the microphone or plays music upon a record player until the neon indicator lamp (upper right) flashes to indicate the proper level. After the level has been set, the control switch is turned to the Record position, at which the projector automatically starts going and recording. However, an accidentalerasure safety switch, at right of the control pointer, also must be depressed as the pointer is moved to the Record position. FULL AUDIO ACCESSORIES The standard projector comes with two input positions — one for the record player and the other for a microphone. Thus, it is possible to record both music and voice at the same time. If the operator wishes to record from two records and a microphone — so that a smooth transition may be made from one record to another — a small mixer is available. This allows sound from several sources to be mixed and recorded. A headphone jack also is provided within the machine, so that a pair of headphones may be used for monitoring purposes. The recording may be made at either silent or sound speed, regardless of the speed at which the film was exposed. However, when the very best audio results are desired, the 24 frame speed is recommended for recording and reproduction comparable to that offered by the better type of home-used tape recorder. Thus, most people will prefer in the future to make their pictures at the 24 frame per second speed. PLAYBACK PROCEDURE Magnetic playback on the Movie-Sound 8 is accomplished in the customary manner: simply rewind and rethread the film, then turn the control switch to the Playback position. This, too, automatically starts the projector. If, on the first run through, any fluffs are found in the recording, it also may be re-recorded in the conventional manner of the magnetic medium, with automatic erasure during the process. NEW HORIZONS AHEAD The economy and simplicity of magnetic sound on film with the Movie-Sound 8 are bound to appeal widely. In the first place, it is not necessary (as it currently is with Sixteen) either to use a special [Continued on page 216]