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360 Systems Digital Keyboard

With real acoustic instrument sounds

Article from Electronics & Music Maker, August 1983

Bob Easton, designer of 360 Systems' new digital keyboard, introduces the review by discussing its development.

"I've been involved in electronic music for about fifteen years and I own one of the very first MiniMoogs that came out, but I'd always really admired traditional instruments. I grew up playing them and naturally turned towards electronic instruments like Mellotrons and Chamberlains as a result. They've been very unavailable to musicians over here for a long time, except in very limited quantity and for ten years I've been planning to make an instrument that would really do a good job on these — where you could select all the real sounds that you wanted put in, play it polyphonically, take it on the road and have it lightweight and reasonable in cost. Above all, you'd have studio quality sound so that you could go on stage and sound good or so that you could work on your own personal music projects and bring all of these wonderful real instruments to your project that you just never would have a chance of learning to play all by yourself.

We had several things that we wanted to do with the 360 that I think we've successfully done. We wanted the quality to be up, so we have a good frequency response and we wanted to do multi-sampling that is across the width of the keyboard. That meant we had to do a very large number of samples so that you don't hear the sound speed up and slow down and go through strange tonal changes as you play up and down the keyboard.

We go into the studio and record all of the notes required from real acoustic instruments, generally using top LA session players in very good studios. At worst, we'll just record notes at minor third intervals — the transpositions are generally very small. There's no fixed drill about it but if you can actually hear the transposition then you went too far.

There may be as many as 24 samples, there may be as few as 4 samples, but you can depress eight keys at any one time. We also felt that it was important that notes go for the length that they really do in the real world. In other words, when you pluck a guitar string or play a piano key, it should decay down to the very bottom of its dynamic range.

The instrument has an extraordinary amount of memory, with two megabytes of address space in it. However, it's not really standard digital recording and it uses some proprietary techniques that give us even better quality and much better memory economy than would be realised if we took the obvious approach, let us say.

We've tried to bring it in at a price point where we thought it would be affordable to a large number of people. We also liked the idea of playing two instruments at one time across a programmable split point, as well as being able to stack any two instruments on top of each other. So we've brought a lot of the orchestration and arranging techniques that happen in the real world to the keyboard. You can't do everything with it, but you could put it under your arm and walk into a club and have a hell of a time! And you can work on your own recording projects with it and bring the excitement, richness and complexity of real acoustic instruments to your own personal projects. We think that it really is going to contribute a lot to the fun of electronic music because it really is a big departure from what's going on with synthesisers — and I think it's a very good complement to them as well. There's been extraordinary interest in it both at home and in the U K. — our first large shipment for England is during the summer.

We have a slightly different approach to our design because we feel that the proper residence for a sound is inside the keyboard, not in your briefcase or in the glove box of your car. We have also found that it is not easy to do what is called 'multi sampling' — to record say twenty notes or even ten notes across the span of a keyboard and have them absolutely identical in performance style, in tonality, in loudness and in length and we go to great expense to do that. Granted, you don't have the flexibility of being able to sample your own sounds, but you don't have the headache either and frankly we're providing everything that the market is asking us to do. When people call us up and say, "you should do this" because that's really what's needed, we're prepared to consider suggestions and if necessary, go into the studio to make the recordings, whereas someone doing that on their own is unlikely to be able to afford the time or the money. For example, I spent £5,000 just recording the strings! When I have to spend that, I could put it on a thousand different instruments, so it's of no consequence.

360 Systems has been in business for about twelve years in Los Angeles, California. It's the originator of the guitar synthesisers, which were subsequently manufactured by Arp Instruments and Roland as we have today. It does manufacturing for other keyboard manufacturers and other musical instrument manufacturers who I'll not name right at the moment so as not to steal their thunder. Its primary endeavour right at the moment is the 360 digital keyboard with its sample sound system. We will be going into the studio soon and recording additional things such as Earth, Wind and Fire 'Brass' with a dozen players — things that you can't get readily on your own, that you can't synthesise and that the whole world loves. We think that there is a richness and a wonderfulness to acoustic instruments that we'd like to bring at a reasonable cost.

All the sounds we list are highly available. We're also planning to do pipe organs, brass patches, large brass sections, other string patches and we are working on a very large choir sound. The choir will be 'aahs' and 'oohs' initially and from that point we will be interested to hear what everyone tells us we should be doing!

We do consider from time to time the possibility of taking other people's sounds recorded on tape to use as samples. Some people are able to produce a large number of samples that are beautifully recorded and brilliantly played and under those circumstances we might listen to them. We basically don't want to invite people to do some thing that's difficult to do and convince them that it's easy, because that's not the case. But we're all ears, we're tremendously interested in the comment of the industry and the whole world in this.

The keyboard is not pressure sensitive or velocity sensitive at present. There's an interesting question about how a wide variety of acoustic instruments should respond to velocity sensing or pressure control. But we've provided hand and foot controls for both the brightness of the sound and the dynamic, the loudness of it. And the foot 'Sustain' actually works much like a piano sustain pedal. It turns out that straight touch sensitivity controlling dynamics alone does not produce a very satisfying result on real instruments. It should do more than that — it would have to change the tonality of them. At some point in time you can be certain that this will happen. You can't have string portamento at the moment, but this is 1983 — ask me that again in 1985!

We found that bringing it in at an affordable price point has been one of the extremely important things for us to do. It's actually quite easy to do something at ten or twenty thousand dollars, yet it's a worthwhile challenge to try to turn out something at under $4,000 and include what we hope will be the important key things.

Even though there are a large number of chips in the machine it doesn't need a fan. It uses at present 64K chips and we will use 256K downstream. There's about 150 of them inside. With the price of memory coming down rapidly this will be a tremendous boon to the music industry because it'll make things better and cheaper as time goes on."

The 360 Digital Keyboard is 8-voice polyphonic and holds up to 32 instruments which are digitally recorded sound samples of selected real instruments. The samples are stored internally on ROM (2764 type) memories, and are therefore immediately available on power switch-on. Unlike other systems that employ 'looping' of a segment within the sample in order to achieve note sustain (and save on the amount of memory needed), the 360 instrument uses full-length notes with no looping or synthesised envelopes. Various performance options are provided and the output is normally stereo (but also mono compatible).

The 360 DK measures 850 x 560 (including heatsink) x 130 (inc. feet) W x D x H mm. Weight is 19.5 kg so it is heavy for its size, yet quite portable by one person. Construction is on a plywood base with similar formers and solid black walnut side pieces and front. The hinged side piece containing the performance wheels, the top hinge metal panel, and the rear panel are metal with strong black vinyl covering. Softer vinyl adhesive strips are used on the labelled sections coloured black and darkish blue with white legending. In hot conditions, at one or two points there was a very slight 'bubbling' on the front panel label, but this could easily be smoothed down with a finger. There's also a noticeable gap of ⅛" between the switch button showing the PCB mounting. Apart from giving an 'unfinished' appearance, it allows dust into the case.

By removing two screws on the lid and lifting it up the extensive circuitry is accessible for making additions or changes to the instrument sounds. At the left end are two top-mounted boards containing the ROM memory chips. The review instrument contained a top board with 16 'miscellaneous' sounds, 11 Horn, 11 Wood, and 5 Jazz. The lower board was used entirely for the new string sample using 48 ROMs (each 64 K). These boards are mounted on a further PCB for data transmission and assignment. A small centre PCB contains a CPU and a logic control circuitry and is linked via ribbon cables to the keyboard, panel controls and data board. The right side PCBs contain the DACs (and 8 MHz crystal clock) plus the PSU components and audio PCB using CEM 3320 filters on each of the 8 notes. (Most chips have their numbers removed!).

Inserting ROMs is simply a matter of locating the specified sockets and inserting correctly — this will usually be carried out by your dealer.

The rear panel carries a large vaned heatsink which runs too hot to touch, an illuminated power on/off switch with socket for mains cable (actually marked 120v for 240v operation!), and slow blow 1A fuse. Five standard jack sockets are provided for foot pedal control of volume or filter, foot switch sustain, and audio out sockets (mono and stereo) giving a strong 1v peak signal. There's also an auxiliary (Var.) socket and a computer interface cut-out may be used for future accessories such as polysequencer, remote or additional keyboards.

The shape of the 360 DK makes it fine for stacking another keyboard on top provided you keep the rear ventilation holes clear — especially with no fan for extra cooling in the instrument.

Right hand controls.


Four main sections are located on the front panel for Volume, Filter, Instruments and Format, with a 'performance' controller section to the left of the keyboard. The latter uses standard size keys quite firmly sprung, over 4 octaves from C to C.

Volume. Here we have the main output volume control — a very good signal level is available, although on very high settings some background noise (vibrato oscillation primarily) will be picked upon DI'd output to mixer. Also a Balance control for setting individual levels of two instruments in use together.

Filter. Nine times out of ten, you won't need to switch in the filter as the sounds immediately start to lose the very good clarity on all the samples. Two switch buttons (all buttons have built-in red LED on indication) allow a particular sound to be filtered (low pass cutoff type) and it's probably most often used when a solo or one of a mixed pair needs prominence. The filter is switched off when a new sound is selected. A pedal mix control sets the external pedal (any 10k lin pot type) to a Volume and Filter combination effect. Instruments. The sound selection buttons are in four groups of four and their sounds will be examined later. On the review instrument the last two buttons (15, 16) were inoperative as the new string sound had been included to activate from the Variation button in the next section. It is also possible to access a second memory card if you have more than 16 instruments by holding a button down for more than half a second, with LED showing half brightness.


Some interesting options in this section open up the usefulness of the instrument.

Split. This button allows two instruments to be played together. The split point is normally at B/Middle C in the centre of the keyboard but is easily reassigned by pressing the (upper) split note at the same time as the split button. It's easy to change instrument combinations by simply doing a push to cancel, push to select with the appropriate buttons. A combination of up to 8 notes can still be used in left or right split areas.

Swap. This conveniently exchanges right and left instruments in split mode.

Stack. This allows one instrument to be placed on top of another to sound from each note. Four notes maximum are available in this mode and it makes effective 'one hand' ensemble playing.

Double. This is a special extra voice effect that is assigned differently to each instrument chosen — specifically how much detune is added, and how much delay to start times. As with Stack mode, only four notes are available and it cannot be used as well as Stack or Split. Double creates an 'ensemble' feel to the instrument selected and has sensible 'next-note-played' priority.

Both Stack, Double and new Instrument selection can be activated during a note or chord and won't come on until the next key is played. This allows a long sax note, for example, to be heard followed by a group of flutes and so on — a nice touch for on-stage playing.

The stereo field actually changes as more instruments or notes are added, so two instruments played at once start at the right and left and fill in towards the centre as more notes are played. When a single line is played, the image stays in stereo centre. As additional keys are played, the stereo space therefore becomes wider.

Transpose. When using Split or Stack modes, it may be desirable to transpose the pitch of one of the chosen instruments. Any interval can be selected by holding the Transpose button and pressing the desired note jump up or down from Middle C. Transpose is also useful for making new chords from your basic ones that you play on the keyboard.

Variation. This button, as mentioned, assigns the new string sound on the review instrument.

Left hand controls.

Left Hand Controls

Four performance controls are situated at the left of the keyboard. Two notched black plastic wheels (neither spring-loaded or with centre detent) provide Pitch Bend and Vibrato.

Pitch Bend from the adequate centre 'dead' position, shifts overall pitch up or down a tone. The way you use it depends entirely on the instrument selected. Quick bends up to sax notes, guitar string bends over the whole range available (resetting instrument overall pitch with the Tuning control), trombone slides around the note and so on are very effective in improving the realism of a traditional instrument.

A Tuning control puts A = 440 at '11 o'clock' setting (with Pitch Bend at centre) and not at centre as stated in the manual. Maximum pitch deviation is one semitone up or down.

Vibrato. Most instruments benefit from the addition of vibrato. This wheel adds sine wave modulation +/- one semitone. It's best added after the note start and taken out before the end of a long note. A Vibrato Speed control sets oscillation from one every 2 secs to 10 Hz approx. The centre settings are the most natural.

In Performance

The approach to playing an instrument with real samples is much more exacting than with standard synthesis instruments. You have to think of the way the particular instrument really plays in performance. Many factors have to be considered, such as pitch bend, vibrato, fingering action, length of notes, dynamics, playing register, solo or ensemble, open or close chording, phrasing, strum, arpeggio or broken chord technique and so on. If I hadn't spent many years conducting orchestras and also playing quite a few acoustic instruments, I would hardly be in a position to accurately assess this sampling machine. After all, the absolute criterion has to be the final sound quality of each sound on the 360 DK.

In general terms, the 360 DK's sound quality is very good indeed, considering the vast amount of circuitry and the problems of getting the samples absolutely right. Once you start doing samples yourself, you realise that a new factor is added to getting your sound right — it's your own ability to choose the most realistic sample for a particular instrument. I can play the keyboard of the 360 and say, "that's not really sax", and then play it on a cassette away from the keyboard and find that I'm convinced it is! Once you start mixing sounds together in a multitrack situation, the realism of individual instruments improves tremendously. (How do you think we've managed so long with so many electric piano sounds!)

Instrument Sounds

Page One of memory is always occupied by the basic collection of sounds the keyboard is shipped with. Page Two offers memory expansion for up to 16 additional instruments to be added. (In the review instrument, Page Two held just the Violin sound). Here are comments on the sounds supplied. Many instruments do not cover the whole keyboard range so remaining notes at top or bottom then automatically duplicate the nearest octave notes.

Vibes. Full 4-octave range. Note lengths: Max 7.5 secs, min 2.8 secs, with wide variation over range dependent on actual or 'transposed' sample being heard on a particular key (all timings except Vibes are from all the Cs available). Five samples. (The number of samples is the reviewer's assessment made both aurally and by examination of 'scope waveforms).

The transposed sample is created by running the digital data of the sample through at a slower or faster rate, thus producing a pitch change up or down. This is a good sample, especially at the low octave, with stick pad hitting the bar and good decay time. It's improved with vibrato.

Electric Bass. 3-octave range (top octave repeated). Note lengths: Max 17.1 secs, Min 6.4 secs. Four samples.

This could almost be a plucked double bass, but it's meant to be electric bass. It's a rich solo sound that's sustained very well. In Double mode it's a great detuned piano-like Bass.

Nylon String Guitar. 3½-octave range (C to F#). Note lengths: Max 7.7secs, Min 1.1 secs. Five samples.

This is the most realistic guitar sound you'll probably hear for a long time to come — even though there are not samples for each string. In fact, the tonal differences between samples — the twangs and resonances — all add true 'more than one' string realism.

Arpeggios are easily done although strums maybe impossible to master. Adding vibrato and pitch bend is desirable and in Double mode it's like having a Spanish Guitar Trio in your living room. The bass is particularly rich, but the upper range should at least go up to the end of the keyboard.

Clavinet. Full 4-octave range. Note lengths: Max 11.9 secs, Min 1.8 secs. Four samples.

This one is a bit fuzzy — more noticeable on decay (especially the second sample up). Top and lower octaves are best, although it's a credible Clavinet that's not over bright.

Electric Piano. Full 4-octave range. Note lengths: Max 11 secs, Min 1.8 secs. 5 samples.

Some say this is a Wurlitzer piano sound, but for me it's a little too bell-like. It also has a stoney quality with a very bright attack. It's particularly clanky on third and fourth samples, more mellow in the bass (with high harmonic ringing) and quite thin at the top. Adding vibrato helps.

French Horn. Full octave range. Note lengths: Max 10.7 secs, Min 6 secs. 6 samples.

A great sound, this one, and you can even hear the horn's pitch gently wavering as a note is held. There's a nice breath release at the end of the sample. Tongueing is clearly evident, with high notes 'opening out' on sustain and bottom notes more puffy and brassy as they should be.

It's a really good mellow solo or ensemble sound that needs delayed vibrato quite often.

Trombone. Full octave range. Note lengths: Max 8.3 secs, Min 3.4 secs. 7 samples.

The lowest octave is breathy (as it should be, but you might notice it changing pitch as well). The top sample has a slight low frequency thump at the start but over the range, the note transition is smooth. The top octave with vibrato is fine for solo and the whole range will make effective ensemble. There is one note that's the real, real thing and that's Ab above Middle C! Pitch Bend can be used to give slide trombone effects and the sound is generally good.

Trumpet. 3-octave range (lowest octave repeated). Note lengths: Max 4.3 secs, Min 4.2 secs. 6 samples.

This is not what I expected. It's a bright, rather thin trumpet, with the third sample especially 'edgy'. I preferred it without vibrato, and the filter does help. In Double mode, there's some nice phasing between chord notes. The attack is rather slow, so you'll not get punching brass from it, only solos or accompanying ensembles.

Piccolo Trumpet. 2½-octave range (C-G). Note lengths: Max 1.5 secs, Min 0.9 secs. 5 samples.

J. S. Bach would have loved this one! It's very good over the limited range provided and has short notes with a gentle release, as the real instrument is hard to blow and better played this way. In Double mode it's a rich and powerful ensemble.

Flute. 2¾-octave range. Note lengths: Max 4.3 secs, Min 4.1 secs. 6 samples.

This is another very good breathy sound that can be effective for solos or ensembles (the latter with Double mode). The top sample almost spits out the note! Low notes are good with gentle vibrato.

360 Systems Keyboard opened up.

Saxophone. 3¾-octave range. Note lengths: Max 4.3 secs, Min 4.2 secs. 7 samples.

This sound gets better as you play it over a long time and add touches of pitch bend and vibrato. The highest notes in 3rd, 4th, 5th and 6th samples are very good indeed. This is one instrument that needs all the samples you can give it (try synthesising a sax!). You can add Double for a big jazzy sax section and vibrato is not often needed.

Oboe. 3-octave range (A-G). Note lengths: Max 9.3 secs, Min 4.7 secs. 5 samples.

This is quite acceptable, although you have to watch the gradual note length changes as you go up the keyboard on held notes. A definite thump is heard at the sample end. Samples 3 and 4 are best, with quite a change from Sample 4 to 5, and vibrato is essential.

English Horn. 3-octave range (C-C). Note lengths: Max 14.8 secs, Min 6.6 secs. 6 samples.

A deep oboe sound that makes an effective ensemble. A clarinet section would probably have been preferable for many people. Breath 'tuning' is evident on the lowest octave sample and tonal differences between samples are also easily picked out.

Jazz Guitar. Full octave range. Note lengths: Max 17.2 secs, Min 4.0 secs. 4 samples.

The longest sample on this realistic jazz bass guitar (with plectrum picked string) is the lowest note, giving it a strong vibrant pluck, and long decay through a steady sinelike wave. Although it's really for solo bass lines, the top octaves are quite good for chords as they are sharp attack sines. It's a sharp metallic funky bass that really punches through. Add Double mode and you've got a chorus bass that's hard to beat. The bottom sample is almost like a twanged piano string!

Bowed Violin. (Super Strings on Page Two). Full octave range. Note lengths: Max 7.8 secs, Min 2.6 secs. 4 samples.

This cannot be played in Split or Stack mode unfortunately for that big orchestral sound. It does, however, replace Cello and Viola sounds that will do these modes. This one sound alone costs £700 to buy! It has quite a slow attack that still copes with fast notes reasonably well. The sound is very 'close' with nice bowed attack — all the rosin pours off! In fact, higher up, instead of the smooth silky strings we've got so used to, we're standing close to a real ensemble.

The bottom sample would have been better done on more samples to avoid 'tuned' bowing effects. The filter can help here, although the character of the rich string section is best without filtering. Solo short notes don't really have a sharp enough attack although in ensemble they're fine.

You definitely have to watch hold times on higher notes, which can make sustained strings a problem. The middle sample has a peculiar extra note in the background after a second or so of sustain that is annoying.

Overall, the sound is definitely the 'real thing', but the points mentioned should not occur on a £700 sample, I'm sure.

Rear connections.


I spent some time in analysing the 360 keyboard as carefully as possible, as it points the way, along with the Emulator and other instruments, to the next generation of sampling machines.

The instrument costs £3,500 (ex-VAT) for the basic instrument containing 16 sounds as mentioned (apart from Violins, which are replaced by Cello and Viola). There is also a very good Grand Piano already in the U.K. that was being played at NAMM, Chicago and costing £700. But it doesn't have touch sensitive dynamics and the range is certainly limiting.

Portamento doesn't appear to be too important on sampling machines at present and wasn't missed, but reverberation (or echo delay) is essential and is not built-in to the instrument's circuitry. There's no noise gating or reduction, so some faint vibrato 'flutter' or oscillation can be detected between playing that could have been avoided. But I'm being over-critical here. Generally, as said before, the sound quality is exceptionally good with no loss of high frequencies often found on other sampling instruments.

Once you've played the 360 keyboard, it undoubtedly becomes a very desirable instrument. If you can possibly afford it, you'll probably buy it!

The 360 Systems Digital Keyboard was kindly loaned by Scenic Sounds Equipment Ltd, (Contact Details).


Sounds already available or planned for the future include: Tympani, mf * * Tympani, fff * Fiddle, country * String section, large * Violin, solo * Viola, solo * Bass Viol, arco * Double Bass, pizzicato * Guitar, steel string acoustic * Guitar, nylon string * Electric Guitar, lead * Electric Guitar, fuzz * Electric Bass, finger picked * Electric Bass, slapped * Grand Piano * Tack Piano * Electric Piano, Wurlitzer * Electric Piano, Rhodes * Electric Piano, DMP * Organ, HB3 * Harpsichord * Celeste * Clavinet * Marimba * Xylophone * Vibes * Trumpet, muted * Trumpet, soft & warm * Trumpet, bright solo * Flugelhorn * Trombone * Trombone, punches * French Horn * Tenor Sax* Tuba * Bass Trombone * Baritone Sax * Tenor Sax * Alto Sax * Soprano Sax * Clarinet * Oboe * Oboe, staccato * English Horn * Flute * Alto Flute * Piccolo * Piccolo Trumpet * Banjo * Harmonica * Percussion, assorted * Caliope, out of tune * Female singer, soprano * Male singers * Steel Drums *

Also featuring gear in this article

Previous Article in this issue

Music to Play

Next article in this issue

Studio Focus

Publisher: Electronics & Music Maker - Music Maker Publications (UK), Future Publishing.

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Electronics & Music Maker - Aug 1983

Gear in this article:

Keyboard > 360 Systems > Digital Keyboard

Review by Mike Beecher

Previous article in this issue:

> Music to Play

Next article in this issue:

> Studio Focus

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