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Viscount RD70

MIDI Data Filer & Sequence Playback Unit By Derek Johnson
Published February 1994

This compact unit will store your MIDI data and play back your sequences for considerably less money than the competition. But does it work? Derek Johnson finds out.

Viscount is a name that should by rights be enjoying great popularity with musicians in search of affordable gear. Their EFX1 and EFX2 effects units (reviewed SOS November 1993) were very good value for money, and have apparently seen healthy sales as a result. This month we're looking at another part of the diverse Viscount range, the RD70, a device which takes a now familiar format (see Alesis' Datadisk and Yamaha's MDF2 amongst others) and offers a 3.5‑inch disk drive dedicated to recording and playing back MIDI information. Viscount's unit comes in a compact half‑rack package, and apart from the rather obvious 3.5 inch, double density MS‑DOS (and therefore ST) compatible disk drive, is equipped with a selection of tape recorder‑like 'transport controls' (play, pause, record, fast forward and rewind), a three‑character LED display, and a variety of editing, tempo and song selection buttons. MIDI connections, a start/stop jack and power supply socket are at the rear.

What It Does

The main job of the RD70 is to record and play back MIDI sequences. Rather handily, it does this in Standard MIDI File Format Type 0 (all MIDI data on one track), making for instant compatibility with the vast majority of software and quite a few hardware sequencers. It has a tempo range of 32‑250bpm, and can store up to 192,000 notes in one recording. Recording is done direct to floppy disk, hence the potentially large sequence file. The user can create custom playback chains, with programmable gaps between songs — perfect for automated gigs. There is also a random playback facility, though I can't really think what practical use it has! Type 1 (multitrack) MIDI Files can be played back by the RD70, but they need to have a Stop command inserted at the end of the sequence to function correctly with the chaining options.

If you own a hardware sequencer that lacks a disk drive (Alesis MMT8, for example) or a similarly inconvenienced 'workstation' synth that sports a sequencer (like the Ensoniq SQ1 or Korg M1), it's possible to record multitrack sequences in real time onto the RD70; it transmits and responds to MIDI clock so it can easily be sync'd up to external devices. The result is a MIDI File Format version of your sequence. This is perfect as a backup, for transporting sequences, and for expanding the capabilities of your sequencer. Syncing the RD70 to your workstation/sequencer would essentially double the number of sequence tracks available (sound sources and MIDI Thru box allowing). Not bad.

Most MIDI data recorders can save MIDI System Exclusive dumps to disk — you don't need a computer and software to store banks of synth patches, drum machine patterns and so on. At first, you'd be forgiven for thinking that the RD70 doesn't actually offer this facility — but you'd be wrong. While the machine records a SysEx dump quite happily, on playback it hiccoughs: the RD70's data buffer appears to be too small. But there is a simple solution: halving the playback tempo takes the strain off the buffer and yields perfect, if slightly slower, results. Note that the RD70 cannot initiate a dump request, but simply records any data that appears at its MIDI Input.

Its Not All Good News...

Downsides to the RD70 include the three‑character display and editing buttons. The display is limited in the information it shows: names or complicated parameters are impossible, so songs are noted with a two‑digit number (01 to 99), bar numbers a three‑digit combination, while parameter names and error reports are communicated in cryptic messages of up to three letters. You'll soon get used to deciphering such offerings as bFl (MIDI buffer full), noS (no song), nCl (no clock selected), and also keeping notes of which song titles correspond to which song numbers on disk. Some parameters are accessed by arcane, multiple button presses, which may be initially confusing for some people. The manual is mostly clear, if occasionally a little Italianate in its expression; one glaring oddity is the statement that: "The MIDI language was originally designed by NASA for scientific purposes, and it is only since 1983 that it has been successfully applied to musical instruments." I must say that one slipped past me somewhere along the way.


The RD70 will appeal to gigging musicians who want to take their sequences on the road and require something more robust than a computer. Providing that no live interaction with the sequences is needed, the RD70 is ideal, being compact, affordable and easy to use (once you crack the multiple button push code and learn the abbreviated display language). Users of disk drive‑free hardware sequencers may also join the queue and the computer‑less can use it for storing synth patches.

The nearest competition to the RD70 is rather more expensive (Yamaha's MDF2 costs £329 and Alesis' now‑discontinued Datadisk SQ retailed around £400), so at £239, Viscount's unit is a good buy. In short, the RD70 does a good job at a price that won't have you selling body parts to science.

We Tried It With...

...various bits of MIDI gear, including the Kawai K1r, the Ensoniq SQ1, the Alesis HR16, and a SysEx dump utility on the Atari ST, to check that data dumps survived intact. Note that Turnkey offer a five‑day, no‑quibble, money‑back guarantee, so if you find the RD70 unsuitable for your needs, you can return it undamaged within five days and be none the worse off! Pretty decent.


  • Easy to use.
  • Compact.
  • Large file size.


  • Cryptic display.
  • Fiddly buttons.


The RD70 offers affordable MIDI File compatibility for the computer challenged, and throws in SysEx storage for good measure