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Crumar Composer Polysynth | |
Article from Electronics & Music Maker, April 1984 |
A four-section synthesiser complete with breath control, tested by Geoff Twigg.
Currently, the Composer occupies the top-of-the-range position in the Crumar line of pro keyboards. It offers a versatile solo synth section in addition to poly, organ and strings sources, and as Geoff Twigg recently discovered, more than a surprise or two besides.
It would seem that the once simple task of going out and buying any sort of instrument is becoming vastly complicated by the headlong rush of technology. Manufacturers are constantly striving towards developing a better, smaller, more flexible keyboard instrument at a lower price than ever. We can only dream of where it will all end, but where does that leave the interested but not-too-technical amateur? Between the wonders of the DX7, with algorithmic FM synthesis, and the Casio VL-Tone's pure, inflexible presets, there are a lot of people who need to be able to make an impressive, full ensemble sound without too much hassle.
This is where the Crumar Composer enters the market, and this is the context in which to judge it. OK, you could buy a Poly-800 for the same money - 50 memories and extreme flexibility, plus a sequencer - but a lot of people prefer a simple, single multi-purpose keyboard with enough variety for the user not to get bored with it in an hour and not so much in the way of controls to daunt him at the start.
The first time I came across one particular digital synth, for instance, was in a recording studio on the south coast. I had asked the band to hire a synth for me, and when we got it I was horrified to see that it was totally without instructions or guidance of any kind, apart from the cryptic clues on each touch-sensitive panel. Of course, I've since worked out how to achieve the desired effect, but it cost us quite a lot of expensive studio time just fiddling with the numerous controls and on a couple of tracks we had to settle for second-best. On that occasion I would have been rather pleased to have had a Crumar Composer; and it would have done the job admirably.
The Composer is a fully polyphonic instrument, well designed in the Italian tradition, and weighs around 38lbs - that's at least heavy enough to warrant taking the lift rather than trying to struggle upstairs with it. It's very sturdy, and I reckon should stand the rigours of life on the road very well. The controls are on a slightly raised, angled panel of metal, with wooden end-pieces. The pots and push-select buttons are colour-coded: yellow for the solo synth, red for the poly, grey for the organ and blue for the string section. These four main sections each have a separate output channel, but are wired initially to a single main output, governed by a master volume control. The mix into this mono output is controlled by a four-channel voice mixer, with sliding faders that also act as separate volume controls for the direct outputs: all outputs are quarter-inch jack sockets. There's a master pitch control on the rear panel, with a range of roughly a fourth either side of concert pitch (A=440).
It must always be difficult for designers of this kind of instrument to decide where to place the performance controls such as pitch-bend, modulation depth and rate, and so on. Crumar have provided two wheels on the Composer, one for pitch-bend on the solo synth, the other for square-wave LFO modulation of pitch on the poly. There's also a rate control for this LFO, but unfortunately no other waveforms. However, the most interesting performance control is the breath controller which is switchable to act upon the combined solo/poly synthesiser VCA and VCF sections, of which more in a moment.
The preset allocation is as follows. Solo: seven presets and access to all parameters on a 'Free' button; Poly: three presets and access to the same Envelope and Filter section as Solo; Strings: one preset sound with variable timbre, sustain, and so on; Organ: four presets plus programmable percussion wave.
This section has one oscillator which can be set to 32', 16', 8' or 4' octave ranges and de-tuned a maximum of approximately one semitone. There is a five-way waveform selector giving a choice of ramp, triangle, square and medium or narrow pulse waves. Next to this is a portamento speed control, which at maximum gives a very slow pitch change of four octaves in six seconds, though no quantisation is available. The solo amplifier section has traditional ADSR envelope controls, and a low-pass filter is also added to the circuit: this can be effected by the envelope shaper. Filter controls are Envelope amount, Cut-off frequency and Resonance, and the latter self-oscillates to reinforce the cut-off point.
There's a two-way keyboard split at Middle C of the four-octave keyboard, so that either half may be dedicated to solo synth alone. There is also a very useful priority assignment which directs the solo synth to left or right; that is, to the highest or lowest key depressed, to emphasise the melody line or bass respectively.
Crumar provide seven preset voices, including some pleasant brass and clarinet sounds, and most of these are quite usable.
These presets are not affected by the waveform selector, ADSR or filter sections, but detuning, footage selection and portamento can be allocated to them. At the right-hand end of the preset bank is a black button marked 'Free' which allows you to set-up and modify totally new sounds. I found the solo synth to be a remarkably flexible instrument, though I would have preferred to have more control of pulse width, perhaps with the opportunity to modulate this using the LFO.
The poly section has two oscillators, on each of which ramp and square wave may be selected. In addition, each oscillator has a Transpose button which lowers them one octave; strangely, a detune control, placed in the middle of the second oscillator section, actually works on oscillator one. It has the effect of lowering the oscillator a maximum of a fourth, or raising it as much as a tritone (augmented fourth). Next to this is a Cancel button, acting on oscillator two. There are three presets for the polysynth section, and again the 'Free' assign button, which routes the poly through the same ADSR and filter stage as the solo synth, with all the benefits and disadvantages this implies.
The Organ section has four separate sounds which are very effective, and to each of these may be added a 4' and/or a 2⅔' percussion stop, with separate volume and decay controls. The organ is provided with a variable-length sustain, and a Rotary Sound System with two speeds. This RSS can be used to obtain some very convincing Leslie effects, especially since when a speed change is selected it takes effect gradually, I know it sounds strange, but it's surprisingly realistic.
The string section is perhaps the most disappointing part of this instrument, though it can be quite useful and effective in filling out the texture of the ensemble. It has two octave settings, 16' and 8', together with controls marked Crescendo, Sustain and Timbre. The first two of these form an attack-release envelope, which responds like all the other sections to the single keyboard trigger. The problem with this system is that a single note moving independently of a held chord can cancel the sustain of all the others, which can be quite an inconvenience.
The Timbre control alters the tone of the strings, though it must be said, not by a very great deal.
The envelope for the string section is, of course, linear and could never sound like a real string instrument; however, with a suitably slow attack time ('crescendo'), it can give a reasonable impression. The actual waveshape used is not unlike that of a string ensemble, but there is an unfortunate phasing effect, impossible to lose, which gives an insistent rhythm in 5/16 time. A further problem is encountered when holding a low to mid-range chord on strings, as distortion becomes clearly audible, due to the oscillators trying to do more than they should...
The Breath Controller consists of 2m. of black plastic tubing with a small mouthpiece fitted to one end. Actually, two tubes and several mouthpieces are included for the purchaser, so that you can let your friends have a go without endangering your/their health! The tube fits onto a small nipple at the rear of the console, next to the main output. There is a three-way switch marked 'solo/off/poly' at the left of the front of the instrument, which directs its use to the ADSR/filter stage of either synth, though not both together; only the Envelope stage of these two sections can be accessed from the Breath Controller.
The amount of control can be set by using the Envelope Amount stage of the filter - on selecting positive envelope control, blowing creates a very pleasant brass-like envelope, while sucking stops the sound almost immediately. Turning the Env. Amount to its negative side gives the reverse effect, which - for reasons that are frankly beyond me - is both more difficult and more exciting to use. I'm looking forward to having a lot of fun with this way of controlling the filter though for the more self-conscious it may be a little too awkward or embarrassing to use on stage. If the user were asked to use a microphone, or a larger mouthpiece mounted in some way, it might be less daunting. I'm sure many in my audience would wonder what I was drinking, or perhaps smoking, through that tube disappearing round the back of the instrument!
The keyboard is nicely weighted, with individual springs for each note that offer a suitable resistance to each touch. The weight and spacing of all notes is remarkably even, and this helps to make the Composer a very pleasant instrument to play. Although its design is not the most up-to-date, with many separate and rather limited ICs instead of larger-scale integration, the sounds and capabilities of the instrument will certainly be more than adequate for many people.
The clear, colour-coded layout of the various sections makes it extremely easy to understand, and to use on stage. It also has enough flexibility for me, at least, to spend several happy hours discovering and re-creating sounds with the solo and polysynths that are still fresh and musical. While many manufacturers are giving us more and more control parameters, digitally produced sound and additive synthesis, there will continue to be a market for, and interest in, simple and effective multi-purpose keyboards. In this market area, the Crumar Composer is certainly worth looking at.
The Crumar Composer can typically be bought for £649 including VAT, and further details should be available from the importers, Chase Musicians, (Contact Details).
Review by Geoff Twigg
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