DTS 70mm

The DTS 70mm digital sound process for motion pictures is designed to play in cinemas that are equipped for 70mm projection and 6-track stereo.

It is a dual system in that the digital audio data is recorded on CD-ROM discs.

A special DTS time code is printed on the 70mm motion picture film (located outside the sprocket holes).  
The DTS system (with matching movie discs loaded) reads the time code and plays the correct sound for each frame of film projected.

Film released in the DTS 70mm format do not have the standard (analogue 6-track sound) magnetic striping, so, analogue sound cannot be used. For fail-safe operation, a second DTS playback unit is required. 

The DTS time code is written outside the sprocket holes where the 70mm two-track magnetic striping normally resides. This allows the useable picture area to be increased to fill the space used by the inner magnetic stripes. The size of the time code on a DTS 70mm print is huge. At 30 mils wide, it is easily visible to the naked eye. Damage by normal scratches does not affect the readers ability to scan time code.

Since the magnetic striping is removed, DTS 70mm prints cannot use analogue sound for backup. Instead, installing a second DTS playback unit is recommended to ensure 100% fail-safe operation. If a malfunction occurs, the main DTS playback unit uses its built-in default circuitry to automatically switch to the second unit. A special time code adapter cable and circuit card connects the two playback units together.

The DTS system provides six channels: left, center, right, split surrounds (or mono surround) and subwoofer. The system is completely automatic and fail-safe in operation requiring no action by the projectionist. The system automatically starts and stops, and tracks film breaks and change overs. Transfer into the process can be made from conventionally mixed analogue or digital soundmasters.

The projectionist inserts the movie disc(s) into the DTS player unit and threads the film through the DTS 70mm time code reader head. Once the film is started, the DTS system checks the keyed serial number in the time code and on the movie disc(s) to assure the correct sound is played with the picture projected.