Lexicon Model 1300
A black box that taught broadcast audio to wait for the picture — and got ABC through two Olympics doing it.
Overview
The Model 1300 is not a studio toy. It is a microprocessor-controlled stereo digital delay synchronizer built for broadcast plants, and everything about it reads that way: digit switches on the front panel, a removable delay configuration control module that can be configured in software or hardware, and an engineering brief that talks about decoding hysteresis frame offset information from video synchronizers rather than about warmth or character. Lexicon designed it to hold lip sync no matter which digital video processors sit in the chain, and to compensate for satellite transmission delays on top of that. The audio path is spec'd for transparency and conforms to the 16-bit standard — a 20 kHz bandwidth with harmonic distortion of less than 0.025%, transformer-balanced inputs and outputs, and input/output levels up to +24 dBm. Recording Engineer (June 1983, p.110) put the delay section at up to two seconds, with a quoted 20 Hz to 20 kHz bandwidth, distortion under 0.025%, dynamic range greater than 90 dB, and channel separation greater than 70 dB.
The delay ranges are where the broadcast intent becomes obvious. Stereo units cover 0 to 340, 680, 1365, or 2048 milliseconds; the mono version of the 1300 stretches to 0 to 680, 1365, 2731, or 4096 milliseconds. Front-panel digit switches set the offset, displayed in either milliseconds or frame units — a small detail that tells you who was standing in front of it at three in the morning.
The story of how the 1300 came to exist is unusually well documented, because ABC's Kevin Dauphinee wrote it up himself. The network had been fighting lip sync since frame synchronizers went wide, and in a typical remote news pickup the video might pass through five of them for an average 83 ms of delay — enough to be plainly objectionable to viewers. ABC's first fix was Lexicon's Model 91, which worked but demanded an operator dial in offsets manually, with what Dauphinee generously called considerable skill and guesswork. ABC asked Lexicon for an enhanced model that could detect the frame offset imparted by a synchronizer and delay the audio automatically. ABC's engineering staff worked alongside Lexicon's management, marketing, and engineering teams on the resulting Model 1300, and the first unit arrived in July 1983, passed all the network's tests, and went straight into service.
What followed was a genuinely remarkable run for a piece of rack gear. More than ten 1300s were deployed at the 1984 Winter Olympics in Sarajevo, where feeds arrived from Yugoslavian host broadcasters in 625-line PAL and had to be converted to 525-line NTSC — a conversion with inherent delay — and the 1300s restored lip sync across the coverage. At the Los Angeles Summer Games the unit supported ABC's decision to broadcast the opening ceremonies in stereo, the network's first live stereo TV broadcast in the U.S. Election night news programming, with its many complex remote pickups, leaned on the 1300 as well.
The unit also earned its place the boring way: Lexicon's own advertising noted the Model 1300 had been evaluated and approved by the ABC, CBS, and NBC network laboratories and was in use at all three facilities. That is marketing copy, not an independent verdict, but it is the kind of claim a manufacturer makes when the reference accounts are real. The decoding side kept expanding too — a later serial control option, an RS-422/RS-232 interface that made both stereo and mono 1300s compatible with the Tektronix 110-S four-field frame synchronizer, was the third Model 1300 variant Lexicon brought to market, joining one that detected video phase differences and another built around delay pulse widths. The standard decoding options across the line included pulse-width, wild-feed genlock, and serial data.
For a collector, the 1300 sits in an odd but interesting corner. It is a professional broadcast tool rather than a musical effects unit, and its value in the field was always as a system component — slaved to a frame synchronizer, it needs no manual adjustment, though the manual delay dialing remains available for compensating additional synchronizers upstream. Units turn up from station liquidations rather than studio sell-offs, and anyone buying one should expect to sort out the configuration module and the decoding scheme before it does anything useful. This is gear that wants documentation and a signal chain, not a shelf. But as a document of the moment when digital audio had to learn to follow video, the Model 1300 is about as direct as it gets — a synchronizer that ABC trusted with the Olympics, and that still explains, better than any brochure, why lip sync is an engineering problem and not an accident.
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