Yamaha MD4S

Portable digital multitrackers are getting ever more sophisticated — and ever more affordable. Hugh Robjohns checks out Yamaha's latest MiniDisc 4‑track.

Yamaha have a good track record in easy‑to‑use semi‑pro multitrack recorders, employing just about every recording medium known to man! Their latest effort is based on the MiniDisc Data format and offers up to 37 minutes of recording time in 4‑track mode with an appropriately equipped built‑in mixer, comprehensive editing and track‑managing functions, and full MIDI MTC and MMC facilities.

The MD4S looks superficially just like any other 4‑track MD recorder, with a mixer section on the left‑hand side and the transport controls and metering on the right. The main channel inputs are mounted on the top surface for ease of patching and the remaining interfaces are tucked away on the rear panel. Every control is clearly labelled and much of the operation of the MD4S can be figured out intuitively — always a sign of a well‑designed product.

Despite the relatively low cost of Yamaha's new multitracker, it incorporates a lot of nice features. The 4‑channel mixer is a quasi‑in‑line design allowing either four main mic/line inputs (with two balanced combi‑jack connectors) or the MD track replays to be processed. There are also a further four line inputs (intended for two stereo effects returns), 3‑band EQ on the four main channels, two aux sends and a stereo cue buss. On mixdown, the four MD tracks can also be combined with four live inputs, and each track is provided with a direct output should you prefer to use an external mixer.

The transport section is just as comprehensively specified. MD Data disks can be formatted for each recording session to accommodate four simultaneous tracks, two tracks or mono, giving 37, 74 or 148 minutes of total recording time respectively (standard audio MiniDiscs will only work in the stereo and mono modes). The transport is equipped with all the necessary auto‑locate, auto‑punch, rehearse and looping functions you could want, and the standard song copy, erase and edit facilities are also provided. A shuttle wheel allows audible 'spooling' to find a wanted section of audio across a wide range of speeds and there is a half‑speed play mode to rehearse fast licks! Unfortunately, however, the half‑speed mode can not be used when synchronising to external MIDI, or during recording — it really is a 'practice' mode only, no cheating allowed! Talking of MIDI, the machine can send and receive MTC and responds to MMC commands, so integration with a MIDI sequencer is very straightforward.

An essential part of any multitrack machine is the ability to perform bounce‑downs between tracks so that recordings of more than, in this case, four parts can be built up. Yamaha have taken advantage of the read‑before‑write capability of MiniDisc, so that a track can be re‑recorded incorporating new material along with whatever was there before. This means that even if you have recorded on all four tracks, they can still be mixed together to a stereo backing track and bounced down on to just two tracks, freeing up the other pair for more overdubs. This process can be continued for quite a few passes with only minor degradation in signal quality due to the conversion between analogue and ATRAC‑coded digital audio formats, and the inherent (but minimal) noise and distortion introduced by the analogue mixer. The disadvantage of this approach, however, is that, should the mix go wrong during the bounce‑down, you can not take another stab at it as the original tracks have been recorded over! Yamaha recommend making a song copy of the original four tracks on the disk before bouncing down, purely to protect your hard work, and this obviously makes a lot of sense. By way of contrast, some other manufacturers of MD multitrackers perform the bounce‑down trick slightly differently by recording the bounced tracks elsewhere on the disk, leaving the original four tracks untouched — you pay your money and take your choice of operating concept really, since both are perfectly workable approaches.

The Tour

The MD4S is essentially very simple and most operations can be figured out without needing to refer to the (typically excellent) manual. The layout and grouping of controls and connectors is all very logical, making the machine a joy to use.

At the top of the front panel are the main signal inputs — the ones that are most likely to be plugged and replugged as a recording is built up. The first two inputs are provided on combi‑jacks, allowing either balanced XLRs or TRS quarter‑inch jacks to be used (phantom power is not available). Inputs three and four are equipped with unbalanced jack sockets only but, like inputs one and two, can accommodate mic‑ or line‑level signals between ‑10 and ‑50dBu. Channels one and two are also equipped with a pair of quarter‑inch TRS jacks adjacent to the combi‑jack connectors and these provide very useful unbalanced insert points. A further four unbalanced jack sockets provide two more stereo line‑level inputs, nominally intended for effects returns with a ‑10dBu operating level.

The rear panel contains the interfaces which are less likely to be changed during a session, and is as simply and clearly laid out as the rest of the machine. A push‑button power switch on the extreme left accompanies the 2‑pole AC mains inlet connector (there are no externally accessible fuses) and the usual trio of MIDI sockets occupies the rightmost section of the connector panel. In between are a flurry of phono sockets and a pair of quarter‑inch jacks, the last providing the two auxiliary sends. Each of the four MD tracks is provided with its own dedicated output on phono sockets, another pair cater for a stereo 2‑track monitor return, and the remaining four provide the main mixer stereo output and a stereo monitoring output. On the front edge of the machine a pair of quarter‑inch jack sockets provides stereo headphone monitoring and a 'Punch I/O' footswitch connection. There are no digital audio connections on the machine at all (unlike Tascam's 564, for instance, which offers S/PDIF output of tracks 1 and 2).

The MD4S is essentially very simple and most operations can be figured out without needing to refer to the (typically excellent) manual.

The mixer is pretty straightforward, with an input gain control at the top, covering a 40dB gain range and obviating the need for a mic/line selector. The button immediately below (which is easily mistaken for a mic/line switch!) is labelled FLIP and selects the live input or corresponding MD track replay as the signal is passed on through the mixer. When the input is selected to the mixer the MD track replay is still available for monitoring (and vice versa), via the Cue bus... which comes next.

The Cue bus is provided with a level and pan control on each channel and can be monitored alone, or in conjunction with the main stereo output from the mixer. The Cue bus signal can also be returned into the stereo mixer, allowing the four MD tracks to be combined with four more live inputs during mixdown. The 3‑band EQ section is very simple, with shelving top and bottom sections (at 10kHz and 100Hz respectively) and a symmetrical peaking mid band centred on 2.5kHz. All three sections offer +/‑15dB of boost or cut, and the knobs have centre detents to identify the flat position. The two aux sends are derived from a single knob where the centre detent is 'off'. Rotating the knob to the left increases the signal level sent to Aux 1, and rotating to the right sends signal to Aux 2. The auxes are both post‑fader sends.

The 'extra' line inputs — channels five to eight — are paired for stereo operation and are provided only with basic level controls. These signals are sent directly to the mixer stereo buss. The monitor and master section of the mixer is equipped with a master stereo fader, a monitor level control (affecting both the rear‑panel monitoring output and the headphone feed), and four push buttons. Three of these buttons select the monitoring sources and can be selected independently, or in combination. The options are 2‑track input, mixer stereo buss, and stereo cue buss. The fourth button routes the cue buss back into the stereo mix bus to extend the number of inputs available at mixdown to 12. As the four mixer channels each have two signal paths, one of which contains the EQ, there is a useful degree of flexibility during mixdown. Either the live input or the corresponding MD replay track can be passed through the equaliser as appropriate.

The transport section of the MD4S is clearly delineated from the mixer facilities, with a neat grouping of transport and related controls below the MD loading slot. Large buttons are provided for the Play, Stop, Record and Rehearse functions, with smaller ones for Pause, Song Search (backwards and forwards), and the Auto‑Punch mode. Further buttons provide In and Out points for the Auto‑Punch operation, set and search markers, and activate the loop and repeat functions. To the right of these transport controls is a large shuttle/data dial with the outer ring performing shuttle operations and an inner dial changing parameter values. This wheel is associated with Enter and Exit keys used to confirm or escape from the various menu operations selected through four further push buttons above the wheel. The Pitch mode allows audio to be recorded or replayed at up to +/‑10 percent of nominal speed, whilst the Adjust button facilitates moving the location of Marks and In or Out points by single ATRAC frame increments of 11.6mS. The Edit button gives access to the facilities associated with naming disks and songs, as well as the usual track and song copy, move, erase, combine and divide functions. The Utility button conjures up menus to set up the MIDI functions, as well as to alter the recording mode and display brightness.

Above these system configuration facilities a couple of further buttons are associated with the display — a peak hold facility and a time mode button which cycles around elapsed, total and remaining time or, if a MIDI tempo map has been programmed, between measure, beat and clock displays. A large disk eject button is also here, and above it are four track arming buttons and a record source selector. Each track on the MiniDisc can be armed independently, but the record source mode applies to all four and selects either a 'Direct' mode (the record signal is taken from the corresponding input gain control) or from the 'bus' or stereo mixer output (left routed to tracks one and three, right to two and four). Again, this simple facility affords a lot of flexibility.

The display section is clear and easy to read, although the four track and stereo output meters lack resolution. The mode indicators are small but clear, as is the timer display. The alphanumeric song number/title display above is also used to present warning messages during operation, as well as options and parameters during setup and customisation.

In Use

The internal construction is to a very high standard, with the MiniDisc drive and associated electronics completely self‑contained. A power‑supply PCB runs along the rear of the machine, with the mixer electronics mounted on a large circuit board immediately below the front‑panel mixer controls. Most of the control functions appear to be contained on another large card mounted on top of the mixer board — all very neat and serviceable.

Using the MD4S was great fun and reminded me of my carefree musical days playing with cassette multitrackers. The machine is completely geared up to recording music without too much technological interference. The only slightly tricky thing was getting my head around the functionality of the Flip switch and the way signals were routed to the Cue bus, but once I had grasped the concept, using the machine was simple. Recording and overdubbing the first four tracks was a complete doddle and, after making a safety copy of the first pass, bouncing the four tracks down to two to add further overdubs was no harder. Loss of quality through the first few bounce‑downs was barely noticeable, although it did begin to degrade with further generations — but nothing like as badly as on cassette multitrackers, and even some semi‑pro open‑reel multitrack recorders I have used! I tried a 12‑track recording (five record passes and four bounce‑downs) and the sound remained usable, although the original tracks were obviously not as crisp and clear as when they started out.

Using the MD4S was great fun and reminded me of my carefree musical days playing with cassette multitrackers. The machine is completely geared up to recording music without too much technological interference.

In practice, however, I suspect most users would not get involved in too many bounce‑down passes, as one of the main strengths of the machine is its capacity for integration with a sequencer. Using the MD4S to record the acoustic tracks — voice and guitar, say — whilst following MTC and MMC from a sequencer full of synth parts is a very effective way to work. Backing harmonies and multiple guitar lines could easily be overdubbed and bounced down to produce very good results indeed.

My colleague saw the MD4S as a convenient musical 'scratch pad' on which to try out new ideas by making simple recordings of voice and guitar, overdubbing extra parts and harmonies as required to turn an inspiration into reality. It avoids the need to go out to the studio, power up all the equipment, spend ages programming synth modules and configuring MIDI channels, all just to do a bit of musical 'doodling'. He found that by taking much of the technology out of the process of making music, his mind became better focused on what he wanted to create and in the short time I left the Yamaha multitracker with him, he managed to rough out two new songs to a reasonable demo standard! The best part is that these demo tracks can then be used in conjunction with the full‑on MIDI studio setup when the rest of the orchestration is added (assuming you can maintain reliable timing during the original recordings, of course...).

Conclusion

I was impressed with Yamaha's MD4S. Having used most of the current crop of MiniDisc multitrackers, I have reached the conclusion that choosing one over another has more to do with personal preferences in the way you want to work than issues of audio quality or technical facilities. The Yamaha's inputs are certainly not the quietest around, but nor are they the noisiest, and using a high‑output microphone helps a great deal — I would recommend one of the mid‑price high‑output electrets currently on the market, as I obtained quite reasonable results this way.

The MD4S's reliance on the user copying songs before bouncing down is shared with the Sony MD multitracker. Personally, I think this approach is fine and encourages the user to protect work in progress. However, the Tascam equivalent automatically creates a new song when bounce‑downs are performed, making for faster working with less technical input required from the user.

In terms of the general operation of the MD4S, and the overall facilities of the mixer, transport, and MIDI interfacing, there is nothing to level serious criticism at. It is easy to use, works well, and does exactly what is expected of it.