Toshiba DX-900
A VHS deck that recorded digital audio, digital video, and five separate audio channels. The kind of machine a studio bought two of.
Overview
The DX-900 only makes sense once you know what it was for. Toshiba built it as a videocassette recorder with digital audio, digital video, and on-screen light-pen programming. It carried five audio channels: two PCM digital, two VHS Hi-Fi, and one longitudinal "normal" track. So it was a VCR that doubled as a multitrack digital audio deck, at a time when studios were still working out how to get clean digital sound onto affordable tape.
The video side was not an afterthought. Digital picture processing let viewers freeze up to four images on screen, and the built-in PCM processor handled record and playback of digital sound. HiFi-Stereo (July 1987, p.53) singled out that combination, noting that the digital picture processing improved special effects while the PCM section did the audio work. The light-pen programming was the era's answer to on-screen menus. You pointed at the set instead of at a remote full of buttons.
Owners mostly used it to record. The archive's period material shows Treasure Isle Recorders in Nashville picking up two DX-900 digital Hi-Fi VHS recorders as part of a studio equipment buy, alongside a Sony PCM 2500A DAT machine and a rack of outboard gear (Recording-Engineer, August 1989, p.48). Braidwood Studios in Metuchen, New Jersey listed a Toshiba DX 900 digital 2-track among its new equipment in the same publication's Northeast roundup. Two separate facilities, two separate updates. Studios were buying these as working tools, and Treasure Isle bought a pair.
The frustration was access. The deck's five audio tracks could not all be reached at once. The PCM, Hi-Fi, and linear tracks each had their own path, and the Audio Select button decided what you heard. One owner wrote to Electronic Musician describing exactly that limitation as the unit's most maddening trait. He then described a modification, worked out with an engineer friend, that gave the linear track its own separate audio in and out, independent of the Audio Select button. That let linear recording of SMPTE or other audio sources happen during PCM and/or Hi-Fi mastering without touching the original design. A Memphis outfit, Modern Mods, advertised a version of the same fix in the magazine's classifieds.
Treat the DX-900 as a studio artifact first and a playback machine second. It is a VHS-format device, so the usual realities of that format apply: heads, belts, and a transport that has to be right before any of the digital circuitry matters. The modification culture around it is documented. The long-term reliability record is not, at least not in the archive's sources. What is documented is that professional rooms bought them, that owners pushed them past their stock routing, and that the five-channel architecture was unusual enough to be worth writing to a magazine about.
eBay Listings
As an eBay Partner, we earn from qualifying purchases. This helps support our independent vintage technology research.