Successor to both the SixTrak and the earlier Prophet 600, the MultiTrak needs an excellent specification if it's to compete in the middle ranks of the polysynth world. Has it got what it takes?

It's now a little more than a year since Sequential (or Sequential Circuits Inc, to give their full but now rarely used title) introduced the SixTrak polysynth to the music markets of the world. It came at a time when the synth arena was still very much feeling the after-effects of a technological earth tremor, the one that accompanied the arrival of Yamaha's DX series of FM digital polysynths. But continuing in the company tradition of flying in the face of synthesiser fashion, Sequential gave the SixTrak a conventional analogue, voltage-controlled internal configuration. However, the SixTrak also saw Sequential going for digital parameter access and additional onboard features in a big way, and most important of all it introduced the concept of 'multi-timbral' sound to the budget synth market.

Specification

To be concise and straightforward for a moment (and with the MultiTrak, it's going to be a rare moment), Sequential's latest is a six-voice, multi-timbral analogue polysynth with a five-octave velocity-sensitive plastic keyboard. Other features are a built-in six-track sequencer identical in layout to the one fitted to the SixTrak and MAX, individual audio outs, a programmable chorus unit, a split-keyboard facility, Sequential's much-praised Stack mode, and an Arpeggiator. In other words, all the facilities of a SixTrak, plus a little more besides.

Those of you who may have cause to bemoan the MAX's lack of a battery-backed-up RAM will be glad to know that all sequences and stack/split assignments are retained through power-down, and as with the SixTrak, a generous 100 voice memories are provided, all of which are fully programmable and storable.

The MultiTrak comes complete with a 100-page operation manual which includes voice charts for all 100 factory presets, a 22-page MIDI Guide giving the instrument's complete MIDI implementation, a foldout instruction card giving a brief but concise overview of how to use the synth (particularly neat, this), and a schematic diagram of the front and rear panels with each area labelled and described. If you get the impression that Sequential mean business when it comes to documentation, award yourself a gold star for perception. Style and format of the pamphlets is consistent with that of previous Sequential user guides, which means both manuals are models of clarity and comprehensiveness. If only every synth came as well documented.

Layout & Operation

With the MultiTrak's front panel layout, Sequential have succeeded in striking a decent balance between multi-functionality and clarity, proving that 'digital access' needn't be a synonym for 'headache'.

From left to right, we find the standard pitch-bend and modulation wheels, the Sequencer (which also doubles as Stack/Split) and Arpeggiate sections, the central Control section (which includes the ubiquitous two-digit LED window and Parameter/Program selector), the Sound Parameter section (tastefully laid out in grey, purple and crimson; eat yer heart out, Habitat - Production Ed), and MIDI, Cassette and Chorus Sections, with Master Volume and Tune controls at the extreme right. There are two user-variable Chorus parameters in the form of Rate and Depth, but whilst Chorus on/off is programmable for each voice, Rate and Depth are not.

Virtually every area of the front panel is liberally dotted with small red LEDs (which greatly ease communication between instrument and musician), whilst unlike that of the SixTrak, the MultiTrak's LED window seems willing to impart information on just about any function's current state at the press of the appropriate button. And as a glance at this review's header photo will tell you, the MultiTrak takes its lead from the MAX in dispensing with Sequential's previously beloved MFI teak furniture look and replacing it with something altogether sleeker and more contemporary.

Actually using the MultiTrak is a refreshingly easy and economical process, due to the above-mentioned clear layout and some sensible, though never excessive, use of multifunction controls. The 40 sound parameters are listed in a 4-by-10 matrix, that is, four parameter groups with 10 parameters in each group. Each set of 10 parameters is further sub-grouped visually, all groupings being logical and (almost) instantly memorable. One button toggles between Program and Parameter modes, and when Parameter mode is chosen, the same switch is used to rotate through the groups. You use a row of 10 buttons underneath the parameters to select a program when in Program mode (logically enough) and a parameter when in Parameter mode (ditto). It's the combination of matrix display and associated LEDs that allows you to manipulate sounds in a structured way very quickly, which isn't bad going for what's still an inherently awkward programming system.

However, there are one or two minus points to be notched up on the imaginary score-board. First of these concerns the (unsprung) pitch-bend wheel, which was annoyingly stiff on the review model: the instrument in question was no pre-production sample, so I fear for the worst. I also find it disappointing that Sequential have stuck with the rather carelessly-implemented range control that besetted the SixTrak's pitch-bend wheel, namely a maximum of a major third up and just under a minor third down. There's really no excuse for not having a pitch-bend wheel implemented with a range that's selectable from a semitone to an octave either side - much like the one on the DX7, in fact.

The sequencer's Speed control is another source of displeasure. It doubles as an External Clock selector when turned extreme anti-clockwise, which is a bit risky - especially when there isn't even a clickstop to help separate one function from the other.

Also worth a mention here is the keyboard, which isn't really playable enough for a synth in the MultiTrak's price bracket. In fact, a quick side-by-side comparison told me I preferred the full travel of the SixTrak's keyboard to the sponginess of the one on the Multitrak. And to think Sequential used to lead the world in this field...

Sounds

Sadly, the MultiTrak's sonic capabilities offer little advance on the SixTrak or the MAX, bar the addition of velocity-sensitivity and a voice-assignable Chorus facility. What that means is that all six voices have their own VCO, VCF and VCA (each with its own envelope generator) together with an LFO. Frankly, I think it's a pity Sequential haven't seen fit to endow their new flagship with some sort of more substantial sonic update, (having two VCOs per voice would have been nice), but having said that, the MultiTrak's factory preset voices are a great improvement on the SixTrak's, and that's without the addition of Chorus. As you might expect, Sequential's in-house programmers have given us a fair number of string, organ, bass and lead sounds, along with all manner of weird (though sometimes not so wonderful) sound effects, plus a rather weak selection of percussion sounds. All in all, it's a bit of a mixed bag. Some of the sounds are lively and dynamic, but others have about as much interest and vitality as a stuffed olive.

Velocity-sensitivity is assignable per voice program, and can be made to affect amplitude, brightness of tone, and vibrato amount. It works downwards from a default maximum amount, the highest amplitude peak allowing the quietest sound, for instance.

About the only addition to the MultiTrak's sound-generating capabilities I haven't mentioned is the extension of the VCO, VCF and VCA envelope generators' attack, decay and release times from 11 seconds to 15 seconds. And that's hardly going to stun everyone into awestruck silence and deep reverence for Sequential' R&D expertise. Ah well, so much for progress.

"The MultiTrak allows a total of four realtime sequences to be held in memory at any one time, with dynamic allocation of a 1600-note capacity."

Sequencer & Arpeggiator

The MultiTrak's sequencer section allows a total of four real-time sequences to be held in memory at any one time, with dynamic allocation of a 1600-note storage capacity. This represents a welcome doubling of the SixTrak's capacity, and as was the case with the SixTrak, one voice is assigned to one part, and each part may have a different voice program. Which, if you've been paying attention, you'll know results in that wonder of modern synth terminology we call multi-timbral music.

Any number of voices up to six can be recorded at one time simply by putting the appropriate tracks into Record mode, though needless to say, all selected tracks have to use the same voice program. Individual tracks can be erased, and the volume level of each track can be adjusted while the sequence is playing back. Pitch-bend and mod wheel usage isn't recorded, but the other side of this particular coin is that you can use either wheel while playing over the top of the sequence as it's replaying, without affecting the sequence itself in any way.

There are several additions to the Sequencer section which make it an altogether more attractive proposition than its SixTrak predecessor. Most notable of these is an Append To function, which allows one sequence to be appended to another. It's a fine example of a facility which can't have been all that difficult to implement, yet increases the flexibility of the sequencer a hundredfold. The possible applications are too numerous to list, but basically it allows a working file to be maintained in one sequence (or how about three working files in three sequences?) which can be added to a master sequence at any time. And just in case you don't like the results of a particular Append, a Truncate function is included which enables a sequence to be truncated at any point; a feature that should also come in handy for tidying up improperly recorded endings.

A prominent metronome beat can be turned on or off at any time during recording, and auto-correction of your playing is possible to the nearest eighth note, 16th note, eighth note triplet or 16th note triplet; a 'hi-res' mode acts as a numbing influence on the auto-correct function, letting the Sequencer record your music exactly the way you play it, warts and all. Another new feature is the ability to erase portions of a sequence, or particular notes from any portion of that sequence, selectively over any number of tracks. Nice one, Sequential.

The result of all this is an eminently useful and usable sequencer which lets you do all the ordering about. With the individual audio outputs and sync-to-tape facility that have been implemented on the MultiTrak (see below), the synth will no doubt become an attractive proposition for small studios and similar environments. That's my feeling, anyway.

For the less creatively inclined, the Multitrak has a built-in Arpeggiator as well, though this offers little new over and above what came with its SixTrak predecessor. There are two modes, Up/down and Assign, with the former giving straightforward ascending and descending reiteration of any held keys, and the latter replaying held keys in the order in which they were pressed, and thereby acting as a sort of mini-sequencer. It therefore follows that rests are not a part of the Arpeggiator's vocabulary, which is a shame. Another problem is that, no matter what mode you're in, the arpeggio is only latched when the Sequencer Record button is pressed whilst the notes are held down. This is where the optional footswitch really becomes a necessity, as without it, any arpeggio is effectively limited to what can be accomplished with one hand in one span, unless you want to have a go at activating the Record button with your nose or some other suitable appendage. Even so, I'm somewhat at a loss to understand how any player can take advantage of the stated maximum of 16 simultaneously-held keys...

Your arpeggio is always assigned to Voice 6, so once you have it merrily chugging away, you can play along using the other five voices and change the sound assigned to those voices at any time (whilst the arpeggio's voice remains fixed). One advance on the SixTrak is that your arpeggio can be transposed whilst it is playing, simply by pressing the Sequencer Record button and the key that's to act as the new root.

Stack & Split

For those of you who don't already know, a Stack is a multiple layering of voices (in this case up to six), each of which can have its own voice program. This allows for the creation of quite complex and varied sonorities, albeit with the inherent disadvantage that only one stack may be played on the keyboard at any given time. With four or more sounds stacked, only monophonic playing is possible, with three sounds two-note playing, and with two sounds three-note playing. A fairly straightforward lesson in voice assignment, really. Ten different Stacks can be stored on the MultiTrak (compared with the SixTrak's two), though the mode's allowance of memory is shared with keyboard split assignments, so that if Position 8 is allocated to a keyboard split, it can't hold a dedicated Stack assignment.

The Split facility allows a keyboard split to be assigned at any point on the keyboard, and any number of voices (up to five) to be assigned to either side of the split point. For a split side to be polyphonic, all voices on that side have to be assigned the same voice program, because as soon as voices are Stacked together, that side becomes monophonic. This means that four voices on one side of a split can't be given a two-voice stack and two-note playing, but then again, who's quibbling?

Interconnections

The SixTrak, you may recall, had a number of shortcomings in this area, none of which were remedied on the MAX. However, on the back panel of the MultiTrak we find such relative exotica as separate audio outputs for each of the six voices, and Tape In and Out sockets for saving and loading data. These latter sockets are particularly useful, as they also allow syncing to tape and to non-MIDI drum machines, for which the MultiTrak expects a clock pulse of 24 pulses per quarter note.

In fact, the Tape sockets allow complete Sequencer and Program data to be saved and loaded individually. Program data saving takes about 50 seconds, whilst Sequencer data saving depends on exactly how much information is actually present. An extra touch that should aid reliability is provided by Sequential's tape interface verification system, which prevents accidental recording over a 'dropout' area on the cassette.

Also to be found on the back panel are the more familiar footswitch socket (the optional pedal can be used for, among other things, controlling sequence record and playback), the ubiquitous MIDI In and Out (but still no Thru - clearly Sequential have got something against it), and a pair of stereo audio outputs, each of which is capable of driving a mono amplifier. It would have been nice to have had each socket on the rear panel labelled at the appropriate place on the rear of the front panel, though. A small point, I know, but it would make life a lot easier for musicians not particularly enamoured of having to look at the rear panel every time they want to make a new connection.

"It's a bit of a mixed bag. Some of the sounds are lively and dynamic, but others have about as much interest and vitality as a stuffed olive."

The MultiTrak has no headphone socket as such, but either of the stereo outputs will drive both sides of a pair of headphones. When any of the individual outs are used, the corresponding voices disappear from the stereo outputs, but this shouldn't be an inconvenience, as anyone using the individual outs will most likely be monitoring from a mixing desk, anyhow.

MIDI Implementation

As I implied earlier, the MultiTrak carries on its manufacturer's tradition of excellent MIDI implementation by offering a number of different MIDI Control options. These are easily summoned from the synth's front panel, and act (a) as high-level implementations of MIDI codes included in the instrument's MIDI spec, and (b) as filters for certain MIDI commands. This strikes me as being a Very Good Idea, and deserves to be developed further. Anyway, the most obvious candidates for such treatment are the MIDI Modes. The MultiTrak can operate in three such modes and one pseudo-mode, all of which are selected by pressing the MIDI Mode button and twiddling the parameter control to get the right value. Mode 0 isn't strictly a MIDI mode, as it simply toggles between enabling and disabling MIDI send and receive. The other modes are Omni On/Mono Off (Mode 1), which enables data to be sent on the Basic Channel and received on all channels (default Basic Channel is set to 3, which is a bit odd); Omni Off/Mono Off (Mode 3), which only recognises messages in the Basic Channel (the MultiTrak can send/receive on any one of the 16 available channels); and Omni Off/Mono On (Mode 4), in which each of the MultiTrak's voices is automatically assigned to one of six adjacent MIDI channels. It's this last mode that offers the most potential for exploitation of the MultiTrak's multi-timbral characteristics, as it enables each track to be sent over a different MIDI channel. Sequential have included a Double Mode function which selects this mode, enables external wheel and program changes, and forces the slave synth into the same configuration and channel number as its master - a very handy addition. Incidentally, Mode 2 (Omni On/Mono On), which assigns all MIDI information to one voice of an instrument, isn't implemented on the MultiTrak.

Other MIDI Control options implemented on the MultiTrak are program change enable/disable (bi-directional), wheel change enable/disable (incoming), and external keyboard pressure enable/disable (incoming - if enabled, this allows a pressure-sensitive keyboard to control the MultiTrak's mod-wheel function). There are also commands for dumping all programs and stacks, all sequences, the current sequence, and the current program via MIDI, while the Local command can be toggled on and off. Offhand, the only non-Sequential synth I can think of which implements a similar set of facilities is Roland's JX8P, so you're looking at a rarity, kid.

Virtually all the above facilities are accessed by pressing the MultiTrak's MIDI Channel button and an appropriate Program/Parameter button - which really is simplicity itself.

MIDI Timing Clock bytes are sent when an Arpeggio or a Sequence is playing, and together with MIDI Start and Stop codes, this means that your sequences and arpeggios can be synchronised with a MIDI drum machine; I used a Yamaha RX11 and Roland TR707 without any hitches, though I imagine Sequential themselves would rather you use one of their own rhythm units, such as the excellent Drumtraks or the forthcoming TOM.

A further, altogether more exciting possibility is synchronising two six-track sequencers to give what's effectively a 12-track recording setup. Sequential's MIDI Implementation manuals are reasonably thorough when it comes to giving details of how to get their products functioning together, but whilst the MultiTrak's MIDI Guide goes into some detail regarding synchronising the MultiTrak with a drum machine, it doesn't discuss synchronising two sequencers at all. There's no immediately apparent way of accomplishing this feat, but discussion with Sequential's technical department in Holland revealed that it is possible to sync any combination of MultiTrak, SixTrak and MAX. This is accomplished by putting the slave instrument into Poly mode and selecting a channel that the master instrument isn't sending on, and then setting the slave to External Sync. The slave will then read only sync information, so all that's left to do before starting the master sequencer is to select the sequences you want to use on master and slave. All in all, I reckon the potential for sequencer expansion these options offer could make a lot of people happy - so long as they don't make the mistake of discarding the old SixTrak to help pay for the new arrival.

Finally on the MIDI front, it's a shame that given the flexible split keyboard facility Sequential have provided on the MultiTrak, no MIDI Control function has been implemented to allow notes on either side of the split to be assigned to a different MIDI channel or channels. After all, the Siel DK80 can do it, and that costs about half as much money.

Conclusions

I've made frequent reference to the SixTrak during the course of this review, and with good reason. It's possible to pick up a SixTrak for around the £500 mark nowadays, and considering that Sequential's RRP for the MultiTrak is set at over three times that (and with dealer discount not likely to knock a great deal off that in the immediate future), you'll need to ponder carefully before considering whether or not to go for what is basically an upgraded SixTrak.

Perhaps the most surprising thing about the MultiTrak, aside from its price-tag, is that Sequential have done little to update their sound circuitry since the SixTrak came out over a year ago. Besides financial competitiveness, it's the sonic flexibility of a synth that determines how it will fare (witness the success of the DX7), and I have a feeling this side of the MultiTrak may let it down. But hang on a moment, we're talking about a multi-timbral synthesiser here, and this feature alone should ensure continued (and deserved) interest in the Sequential way of doing things.

And while other manufacturers have made half-hearted attempts at onboard real- and step-time sequencers, Sequential alone have made the connection between multi-timbrality and multi-part recording, thereby taking things to their logical synthetic conclusion. With the MultiTrak, the company have reaffirmed their faith in this approach, and come up with an infinitely more flexible sequencer as the heart of the system.

Because whereas the SixTrak always made you aware of its limitations, the MultiTrak is an altogether more powerful musical tool. It's friendlier, too, thanks to a more directness on the user interface side of things than its predecessor. The separate audio outputs and the tape interface are both welcome additions, even if some people may still prefer to use a computer/disk MIDI setup. And if you're one of those people, you'll no doubt be interested to know that Sequential have some disk-based MultiTrak software for the Commodore 64 in the offing. Advance reports suggest this will allow sound parameter editing and storage facilities, and increased sequencing capabilities, too.

Bearing in mind my reservations about (a) the sheer cost of the MultiTrak, and (b) Sequential's apparent reluctance to do anything more than tinker with sound-generating circuitry that dates back to the Prophet 600, the machine's onboard facilities are sufficient reason for it to merit serious consideration. It's a synth that won't please all the people all the time, but it makes a pretty good shot at it.

Manufacturer's RRP is £1565 including VAT.

Further details from Sequential (Holland) at (Contact Details). Review model supplied by London Rock Shop.