The first sampling keyboard from Sequential, the Prophet 2000, set the standard for all the 12-bit machines on the market. Will the Prophet 3000 stereo rack sampler do the same for the 16-bit field? Paul Wiffen thinks so.

Whilst the original Prophet keyboards were analogue synthesizers, the release of the Prophet 2000 digital sampler exactly two years ago proved that, having finally made the decision to go digital, Sequential were out to make the best of the then-available technology. So successful were they that they still have the best sounding 12-bit machine on the market (to this reviewer's ears at least). Sure, the Prophet 2000/2002 doesn't have the user-friendliness of the Akai S900, the synthesis of the Korg DSS1, the video monitoring of the Roland S50, or the analogue processing of the Emax. But forget the gimmicks and use your ears; the Prophet has the edge: it's noiseless, equally responsive across its wide bandwidth and the easiest and best for looping.

But technology marches on. Component specifications improve and drop in price, musicians and engineers constantly demand higher performance, more memory, increased facilities and wider applications... and so, two years later you have the Prophet 3000, the next step forward. It is the first affordable 16-bit stereo sampler (if you discount the Synclaviers and Fairlights of this world) and like the Prophet 2000, I suspect it will still be delivering the audible goods long after the flashier looking competition in much larger, more impressive boxes is luring away those who buy with eyes, hearts or pride making the decisions instead of their ears.

For the sound of the Prophet 3000 is perfect transparency. Sampling in stereo from CD, I would defy anyone to tell the difference (indeed, I gather that in a test conducted at a French music store, a highly respected blind musician consistently picked the 3000 as the source, not the sample). Now it may be that as our ears become more atuned to the fidelity of 16-bit systems, we will recognise finer subtleties (I don't mind admitting that the first time I heard the Emulator II, I thought it gave a completely faithful reproduction), but I doubt it somehow! Quote this back at me in two years time if you like, but I suspect that 16-bit, 48kHz sampling is as much as we'll ever need to capture all the subtlety of sound that the human ear can appreciate.

The maximum sampling time of the Prophet 3000 at its highest available sampling rate (48kHz, which gives nigh on a 20kHz audio bandwidth - more than anyone except 14 year-old boys can hear) is 21.8 seconds in mono and half that (10.9 secs) in stereo. This increases to 23.7 secs at the industry standard rate of 44.1 kHz (the sample rate of CD and several other recording formats). These times are, of course, what you get with the unexpanded 2 megabytes of internal memory. The Prophet 3000 can be expanded up to 8 megabytes, which quadruples these sample times, giving over 40 seconds of 48kHz stereo sampling. And for those who find this a bit limiting, a forthcoming direct-to-disk option will make record times of several minutes available. For each megabyte of hard disk memory available, you can record over 10 seconds of mono sound. So a 40 megabyte hard disk will give over 400 seconds of mono playback, ie. 6½ minutes, whereas a 100 megabyte version (the other hard disk size which Sequential will be offering) will give more than 1000 seconds, ie. more than 16 minutes mono, 8 minutes of stereo or, in the four-track recording format Sequential are talking about, 4 minutes of 'quad' (playback only) sound.

But the Prophet 3000 is (for the time being at least) a musical instrument, first and foremost, and it is as a musical instrument that it excels (although when the direct-to-disk option is released at the end of the year, many studios may consider it primarily a digital recorder).

AUTO SAMPLE MAPPING

For the first time on any multi-sampler, there is a default option which automatically maps samples as well as looping them. This means that when you play a sample into the Prophet 3000, it detects the pitch, places it on the nearest key and produces an 'oscillating' loop one or two cycles long at the end of the sample. So, when sampling fairly simple waveforms like a flute or trumpet, for example, you will be able to create a complete looped and mapped preset in seconds instead of minutes. This is a real boon for people like me who are sampling in a time-pressure situation (like an expensive recording studio) and even when the auto-looping doesn't come up with a perfect result, it at least gives you something to work with quickly. The only thing you will have to do for yourself is fine tune the samples, but the Prophet gives you an A (440Hz) tone to help with this, so you shouldn't get tied up for too long with tuning.

Of course, auto-looping over just one or two cycles at the end of a sound is fine for less complex waveforms, but it's not going to give you much of a result on a sample of thirty violinists playing together, or a changing synth timbre, so the 3000 allows you to either edit those loops and maps automatically set up by the machine, or by using 'User Mapping' create both yourself. However, the 5" by 1½" backlit LCD on the remote unit means that you can see exactly the status of the maps across an 8-octave MIDI keyboard range (see Photo 1) or the waveform you are editing with complete control of horizontal and vertical zoom (see Photo 2).

The screen resolution of this LCD is such that you get as clear a picture of the waveform as that obtained when using a Macintosh computer with Digidesign sample editing software, say. As yet, Sequential don't offer the Loop Window facility which both Digidesign's Sound Designer software and the Roland S50 have, but I'm sure this is only a matter of time (for those of you who are not familiar with this concept, the Loop Window places the end of the sample loop against the front of the loop so that you can see that there is a good match of the waveform at these crucial points).

What is far more important than this which Sequential have done, is given you the ability to step through zero-crossings. This feature revolutionised looping for me when it first became available on the Prophet 2000 and no-one else has yet made this flexibility available. It is better than the standard auto-loops on most samplers as it allows you to scan through a whole host of zero-crossing points, independently at the start and end of the loop, and pick the one which sounds best to you, instead of being at the mercy of whichever combination the sampler picks for you, as on other machines. When developing sample libraries for different machines, I always did my sampling and looping on the Prophet 2000 and then used Digidesign's software to send the samples to whatever other machine I wanted them to end up on.

The only thing that the Prophet 3000 lacks in comparison to the 2000 is the automatic cycling of the loop so that you can hear exactly how every change you make to the start and end points affects the loop. I missed this feature badly on the Studio 440, with the end result that I still do all my sampling of musical sounds which need loops on the Prophet 2000, loop them there and then transfer them to the 440. With those machines it doesn't matter of course, as the sample fidelity is exactly the same, but it would be a shame for the Prophet 3000 to have that extra fidelity and yet lose one of the best features of the 2000. Still, I'm sure that if enough Prophet 2000 owners complain, Sequential will soon add the ability to hear just the loop while you're editing it, perhaps with the addition of being able to change the pitch from a MIDI keyboard, to check that the loop is good over the sample's entire range (we have got Sequential's Product Specialist, John Bowen, on our side for this one!).

Talking of the sample's entire range, I have another little complaint here. Because of a hardware limitation (presumably in the maximum playback rate), the highest pitch transposition you can get out of a 48kHz sample is a major sixth above the original (you have a full two octaves below, with much less aliasing than ever before). Now this is quite understandable and indeed improves on the Prophet 2000, which would only handle a fifth above at its 42kHz maximum sample rate. What is silly is that, for the moment at least, all the samples made at lower rates are restricted to the same major sixth higher range. I calculate that for the same replay limit, you should be able to get a major seventh on 44.1 kHz samples and well over an octave on 32kHz samples. As you would probably make most instrument samples at these rates (keeping 48kHz for the more critical job of sampling full musical recordings), it would really be worth having the extra range available. Let's hope Sequential get around to making this possible fairly soon.

For the time being then, you have a 2½ octave range on each sample and as this is heavily biased in favour of downward transposition, it is best to sample those notes near the top of the range you want to cover. When you use the automatic mapping feature, the Prophet 3000 places this full range on the keyboard until the ranges start overlapping, when priority is then given to the nearest original pitch key. You can, of course, override this yourself to make for smoother transitions between multisamples, but on the whole this automatic process gives excellent results.

LOOPING AIDS

As far as sample looping goes, the problem is somewhat trickier, but if neither the automatic looping function nor your manual efforts produce an acceptable result, then Sequential have thoughtfully provided two more weapons to help.

Firstly, you can try crossfade looping, which actually alters the waveform data to smooth out clicking problems (a feature now available on Digidesign, Emax, S900 [Version 2 software] as well as the Prophet 2000/2002 [Version 4 software] and the Studio 440). Now while this often produces an inaudible loop, I have often found that it can introduce a volume fluctuation which gives the looped sample a sort of tremolo effect. Sequential are the first people to help you out of this one by offering Loop Compression. This 'normalises' the amplitude (level) of the sample across the loop, thereby giving you the advantages of crossfade looping without the drawbacks. It is also useful for non-crossfade loops on samples which are dying away (any percussive envelopes like piano, guitar, tuned percussion, etc), to create a level loop so that you can then use the amplifier envelope to reduce the volume.

Whilst talking about envelopes, it is worth mentioning that this is another area of the Prophet machine which benefits greatly from the ability to see the parameters visualised in the display (see Photo 3). I know that Rate/Level envelopes such as the Prophet 3000 boasts (three of them per voice) are better than ADSRs, especially when they boast five stages with two alternate release values, but I've always preferred ADSRs because it's easier to grasp a mental picture of what's going on. Now, with the ability to see what the five-stage Rate/Level envelope looks like, it'll be easier for boring old f**ts like me to get them to do what I want!

On the Prophet 3000, one of the three envelopes is 'hard-wired' to control the volume (VCA) of each voice, but the other two can be sent to the 24dB per octave filter cut-off, the pan position, or any other of the 16 destinations available. There are six other modulation sources to choose from including velocity, pressure, pitch and modulation wheel, plus two MIDI-assignable controllers which could be made to respond to, say, Yamaha breath control or Roland joystick data - whatever you want. This sort of modulation flexibility is more normally associated with synths like the Oberheim Matrix but now Sequential have added this to a state-of-the-art sampler. Clearly there is not room in this already lengthy review to examine all the modulation possibilities, but suffice it to say that I couldn't see anything I've ever wanted to do that the machine wouldn't let me!

Whilst editing a preset, you have the ability to work on all the samples (see Photo 1) or just one of them (see Photo 5). This will depend on whether you are adjusting parameters common to the whole 'instrument' you are creating or simply tailoring individual sample characteristics so that that sample fits more 'invisibly' within the preset. Whichever way you want to work is fine by Sequential.

Once you have created presets (typically each preset might be used to represent a different instrument), you can instantly begin to combine them to make more complex presets. These are stored in exactly the same way as ordinary presets so that you don't need to keep swapping between a 'performance' and a 'single' mode like on a DX7II, for example. Any preset, simple or complex, can be instantly called up, either from the remote control pad, or via an external MIDI program change (sent by a sequencer, say).

Any two presets can be instantly combined to allow splitting, layering or crossfading (velocity or positional) and the levels of each can be set independently, as can the MIDI velocity or note number at which they will switch. For those who prefer greater complexity, it is possible to define just how many presets you want to combine to make your more complex combinations possible. At least 16 presets can be combined into one (anyone out there need more than that?) and then their key ranges, crossfades, velocity control, etc, etc, can be programmed accordingly (see Photo 6).

The Prophet 3000 allows for storage of 9,999 presets, each of which can hold 64 multi-samples. The number of sample locations available was tricky to discover, but it seems to stretch well into the hundreds. Sequential say that their intention is to put an end to all the comparison games of how many presets and samples there are, and I think they probably have, perhaps with a comfortable margin. Still, I'm sure there will be one person out there who'll want to put 65 samples in a preset or need that 10,000th preset. But for the average user I think this will be ten times more than necessary (especially as you can combine presets).

MEMORY RAMIFICATIONS

The basic Prophet 3000 model comes with a generous 2 megabytes (1 megaword for a 16-bit machine) of memory housed in the rack-mount unit and this can be expanded up to 8 megabytes internally. This is unprecedented for a machine in this price range, but unfortunately such memory size does bring problems with it...

The 3000 comes equipped with the very latest quad-density (twice double-sided double-density) 3½" disk drive, but even these floppy disks can only store 1.6 megabytes, so to save a full 2 megabytes worth of sample data you need to use two of these disks. Sequential make the best of this by putting the Prophet 3000's operating system and 0.4 megabytes of sample data on one disk and the other 1.6 megabytes of data on the second disk. Loading from scratch with two floppies takes the best part of two minutes, but once the operating system has been loaded you can choose to load just one or two presets, thereby keeping the load time to a minimum. It is still a bit of a pain though (no criticism of Sequential here, just of the limitations of floppy disks). Imagine how long it's going to take to load a machine expanded to the full 8 megabytes!

Another problem, which Casio FZ1 owners will sympathise with I'm sure, is the price of these quad density disks. At around £8 each, they will soon knock a hole in your disk budget! Still, it's much better than having to use four floppies to load the machine.

Those of you who are familiar with my previous reviews of samplers will know that I am normally quite hard on machines that have to load their operating system from disk, for reasons of security and speed. But I'm not letting Sequential off lightly just for reasons of bias or change of heart. Firstly, their operating system is much larger - it has to be to do all those wonderful graphic displays and automatic functions - but, more importantly, they are working on the cure for all the above problems.

Access time to and from hard disk via the SCSI (Small Computer Systems Interface) port is much shorter, by a factor of 50. Sequential reckon that it will be possible to load 2 megabytes of data in as many seconds from hard disk. This means that a fully expanded 8 megabyte Prophet 3000 could load its operating system and all sample memory in less than 10 seconds and that the basic 2 meg model could manage it in about two seconds. Add to this the facts that Sequential plan to make the operating system and first bank of sounds load automatically on power-up, and that the 3000 would be able to load the next bank of sounds via the SCSI while you are still playing the first bank, and suddenly hard disk storage starts to look like the answer not just to the problems of large memory capacity, but to that of all budget sampling machines, ie. you can't get a peep out of them while you are loading sounds. A two second load time which you can keep playing through - now doesn't that sound like heaven?

Well, that's exactly what Sequential are working on now that they've released the 3000. The plan is to have a rack-mount chassis which will sit next to the present 2U 'brain' of the 3000 and hold two hard disks, either 40 or 100 megabytes each. That means you could have up to 200 megabytes available in one rack-mount chassis! And as the SCSI spec allows for eight devices, this would allow you to have 700 meg on-line (financial resources permitting, of course!). In the direct-to-disk application, this would give almost an hour of stereo recording, or in banks of 2 meg, 350 set-ups of the Prophet 3000.

Sequential hope to have the hard disk usage available by the end of the year in both the direct-to-disk and bulk storage formats. No price is available as yet for Sequential's hard disks, but you can be sure that they will cost more than similar size models for stay-at-home personal computers like the Mac or Atari ST. And so they should if Sequential are making them rack-mounting and roadworthy, like Oberheim have done with their HDX series for the DPX1. People have to learn that home computer equipment is not designed to withstand the rigours of the road. For studio use, perhaps Sequential would do better to make the Prophet 3000 work with off-the-shelf hard disks as well, where the emphasis would be on storage capacity rather than roadworthiness.

Of course, this means you are going to have to make back-up copies of all the sample data on your hard disks to floppy disks anyway (unless you can afford to back-up with hard disks as well), but this will only be for safety precautions and you will not need to bear the disadvantage of using floppies in pressure situations.

FUTURE EXPANSION

The basic Prophet 3000 is an 8-voice machine with both stereo and eight separate outputs. There will be an 8-voice expander which will sell for roughly half the price of the main unit, to allow a 16-voice system to be put together for around £5000. There is also talk of a replay-only unit with no sample inputs on the front, which could function as a standalone unit (Oberheim DPX1-style) as well as an 8-voice expander. It may well also be possible to control several Prophet 3000s and/or expanders from one remote control panel, thanks to SCSI. This would mean you could configure a system (of up to eight components) to suit your needs from the Prophet 3000, expanders and hard disks available. The direct-to-disk software is planned to be available in a 4-track configuration by the end of this year.

On the software front there are several other options planned. One of the most important as far as I'm concerned, and next after hard disks on Sequential's priority list I am told, is a conversion routine for Prophet 2000 and Studio 440 disks. This will mean that the extensive sample library which has developed for both these machines will be available for use on the Prophet 3000 as well. Of course, these samples will not be quite as good as those made on the Prophet 3000 itself but, as I've stated before many times, I think 12-bit/30kHz+ sampling is plenty good enough for sampling all but the trickiest of sounds and full mixed music tracks.

As far as factory disks are concerned, Sequential plan to deliver the 3000 with four sets of two disks covering the usual ground of piano, strings, brass and choir. Of these, I have only heard the piano disk in an unfinished form, but it sounded pretty damn good to me. Sequential then plan to turn the hundreds of hours of F1 digital recordings they have into a comprehensive library which will be sold in sets as the Studio 440 library has been.

Future software is also planned to allow additive synthesis and waveform drawing (for those who prefer to spend time making up sounds instead of recording them). This will no doubt make good use of Sequential's version of the alpha dial on the remote unit for both adjusting the levels of harmonics and for drawing and editing waveforms. The digital signal processing, which at present only covers crossfade looping and compression, will be expanded to cover such features as chorus, delay and maybe even reverb, all of which will be stored as converted samples requiring no real-time processing in playback. 'Hard sync', as found on the old Prophet synths, is another facility they plan to add. Other possibilities include SMPTE and MTC (MIDI Timecode) cue lists, which would add to the Prophet 3000's desirability as a studio system.

CONCLUSION

Sequential are very committed to making the Prophet 3000 a major part of their product line for at least the next two years (well, the Prophet 2000 has lasted that long thanks to their continuous updating) and it looks like it will form a sound basis for a complete 16-bit digital system to cover sampling, synthesis, signal processing, and recording in a way which would have been unthinkable just a few years ago.

The sound quality is definitely there, as is the user-friendliness (the lack of which may have been Sequential's downfall in the past). When the hard disk systems and the various software packages arrive at the end of the year (when the basic versions of more expensive rival systems look like being released), the Prophet 3000 may well be so far ahead of the competition that they never catch up.

Price £3,795 inc VAT.

Contact Sequential Europe, (Contact Details).