DiscoVision Mastering
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IVC 9000 Video Tape Recorder

Before MCA DiscoVision, films shown on television or videotape were transfered on what was known as a 'film-chain' - simply put, a film-chain is just a projector and screen with a video camera pointed at it. While this can give pretty good results, the best results are achieved with a flying-spot scanner, where an electron beam scans the film frame and converts it to video. MCA DiscoVision was the first company to use the flying-spot scanner for thier videodisc transfers. Because of this, many of thier videodiscs still have state-of-the-art tranfers today - titles like DRACULA and PSYCHO look better than their modern DVD counterparts.
In addition to the flying-spot scanner, MCA used only the best videotape recorder to master films, International Video Corporations IVC 9000 VTR.

The IVC 9000 is considered by many to be the best analog VTR ever built. This machine was designed from the ground up to be high performance everything. It's design was borrowed heavily from the Ampex AVR-1. Like it's quad 'cousin', the 9000 featured vaccuum columns, and a vaccuum capstan. The small scanner and the half-wrap of the tape made for a much more forgiving segmented tape format with 57 lines per segment. The control head was also mounted on the scanner for better video tracking accuracy. The timebase stability of this transport design was good enough that an analog timebase corrector was adequate. This format was eventually sqeezed down, and became the basis for SMPTE inch type B! It has been said of the IVC 9000 that you could go down 29 generations and still produce broadcast spec. Even if this is just half true, the machine's performance is on a par with today's digital VTRs.

Video bandwidth was 8MHz, for 640 lines of horizontal resolution. Three discrete channels of audio, S/N 65db, freq. resp. 40 - 15kHz. Linear tape speed, 8 IPS. Scanner speed, 9000 RPM. Relative tape speed, 1,500 IPS.

As you can see, the IVC 9000 produced masters which were well up to the task of making a videodisc. While the audio spec's arn't up to what analog CX LD can do, they are certainly better than the 35mm optical stereo tracks used for mastering. (Note: There are some who claim MCA used mag-interlock tracks for audio mastering, but evidence from the discs themselves shows this to be incorrect - optical track ticks and pops are plainly audible - and these are clearly NOT ticks and pops due to the poor pressing quality of MCA's discs)

IVC did too good of a job designing the 9000 machine. After producing just 65 of these magnificent machines, the leftover R and D costs put them out of business.  In later years, MCA wanted to play some of the DiscoVision master tapes for various reasons, but could not do so since there were no working IVC 9000 VTR's to play them on, making the tapes almost worthless. In fact, all evidence indicates that MCA and Pioneer destroyed all the MCA DiscoVision master tapes and master discs.

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IVC 9000 VTR used for all DiscoVision mastering