Up until about three years ago there were really only two companies producing synthesisers in a big way. One was Moog Music and the other was ARP. Back in October we ran an article entitled The Moog Story which proved to be extremely popular, so this month we've decided to examine ARP, the other of the 'big two'. I'll look back at ARP's history, the present situation, and what is to come in the future. To me, ARP can be summed up as following a policy of 'wait and see, try and do it better, try and do it cheaper, update it, change it'. I think that these phrases will become clearer as we go on.

ARP started relatively late in the day in terms of the electronic music industry. It was not until 1969 that Alan R Pearlman (hence ARP), an engineer, businessman, and keen musician, sold his successful industrial electronics firm and turned his attentions towards musical electronics. Pearlman had closely followed the trends and developments in electronic music ever since his school days in Worcester, Massachusetts, and had set his heart on turning the inventions of people such as Moog and Buchla into instruments that could be played by musicians instead of engineers.

With the aid of David Friend (ARP's present President), a Yale graduate with considerable experience in the electronic music industry, and a team of designers, wirers and the like, Pearlman and his company proceeded to design and build a huge studio synthesiser, which was completed in May 1970 and known as the ARP 2500.

ARP's late entry into the synthesiser business seemed to be reflected in the designs that they were producing. They could evaluate the problems that musicians were having with synthesisers and solve them on the instruments they built. A good example of this can be seen with the 2500 synthesiser. Earlier studio synthesisers looked more like telephone exchanges than musical instruments; this was the result of using 'patch cords' to route signals round various modules. However, with the 2500 these patch chords had been replaced with a matrix patching system using scores of rows of slider switches (above and below the racked modules in the photograph) which kept the instrument from looking like a spaghetti tree. This sort of design philosophy was dubbed 'human engineering' by David Friend.

Following up this successful studio machine ARP proceeded to develop more portable, less expensive instruments. 1971 brought an early version of the ever popular ARP 2600, a lightweight and extremely flexible performance synthesiser. The instrument was 'pre-patched', which enabled the performer to set up various sounds without the use of patch cords, but which could also be patched with cords to override the prewired circuitry. The 2600 is one of those classic instruments that never ceases to be popular.

ARP's products mostly fall into two categories: variable and preset. The variable instruments (those currently in production being the Axxe, the Odyssey, the 2600 and the Avatar guitar synthesiser) use continuously variable controls for all the parameters that go into making up the sound. The preset instruments (namely the Pro Soloist and String Ensemble, followed more recently by the Pro/DGX and the Omni-1 and Omni-2), as the name implies, have preprogrammed sounds which can be obtained at the flick of a switch or the touch of a button, and can usually be modified to some extent. The new Quadra is a polyphonic instrument that falls into both categories, being continuously variable but also having the facility to preset required sounds.

Before we look at the individual instruments more closely, I would like to examine ARP's design policy a little more. David Friend was quoted as saying, 'I think a really good instrument has to have a lot of compromises. The end result is that you get a lot of things with marginal use at great expense.' This seems to be ARP's approach when designing an instrument: they start with an instrument having all the frills, everything, and then start throwing things out that are not cost-effective. This sounds very much like the policy of commerce and very much alien to musicians - their ideals, and 'the art' — but it does make some sense. Why pay for things that do little and cost a lot? ARP constantly update all their instruments — sometimes, however, for the worse.

For example, one of the most dramatic series of changes is evident when you look at the styling, design and finish to the casework of the instruments. To start with, the instruments in the ARP range were styled with a white fascia. Then the styling was changed to include a black fascia; the rotary pitch benders were replaced by proportional pitch control (ppc) white pressure pads. Then the whole casework took a dramatic change for the worse: a black and red fascia, overhanging keys (being totally unprotected and just asking to be broken off), and cheap, almost hardboard endcheeks. This series of changes to the instruments enables one to instantly assess roughly how old each instrument is; this can be both advantageous and disadvantageous to someone buying/selling a secondhand instrument.

So, bearing in mind the ARP design philosophy, let's now look at the individual instruments currently (or soon to be) featured in the ARP catalogue.

The Axxe is the baby of the range. One VCO; one VCF; a low frequency oscillator (LFO); noise, sample and hold; and an ADSR envelope generator are the main features of this neat little instrument. It is very light, easy to use, and quite good (if rather thin) lead-synth sounds can be produced. For pitch bending, as I mentioned earlier, ARP have developed the proportional pitch control, in the form of a white rubber pad, which either bends the note up, down, or introduces LFO modulation (selected by a small slide switch above the ppc). The harder this pad is pressed, the more the note is affected. Some people don't like this system, but I find it rather pleasing to use, and also more reliable than other systems. The Axxe is a good, reasonably priced instrument for those with a small budget. My only major criticism, as I mentioned earlier, is the styling of the latest model. Those overhanging keys and endcheeks leave a lot to be desired.

The Odyssey is the Minimoog's greatest rival, and is the best known of the ARP range. Some people swear by the Odyssey, some by the Minimoog; they both have their own characteristic sound, and both possess certain features not found on the other. The Odyssey sound is more cutting and not as warm as that of the Minimoog and, in my opinion, is most at home in the jazz-rock field. It consists of: two VCOs; one VCF; one LFO; noise, sample and hold, delay; an ADSR envelope; an AR envelope and three separate ppc pads: bend up, LFO modulation, bend down.

Again, if considering buying an Odyssey, I would go for the last but one model with the back fascia and protected keys.

Along with the Odyssey, the 2600 has become a standard. It can be used with ease when playing live, and is also a very versatile studio synthesiser. The main features of the 2600 include: three VCOs; one VCF; noise generator; sample and hold; an ADSR envelope; an AR envelope; reverb; and a built-in stereo amplifier with monitor speakers. The keyboard, which has been updated from the original, is now duophonic and is separate from the main console. As with the previous two instruments, sliders are used for the controls. These make it much easier to see what is happening but can be more difficult than rotary knobs to position exactly. I mentioned earlier that the various modules that make up this instrument are prewired to give the usual synthesiser routing patterns, but that these can be changed by using patch cords to give almost any combination. A rather expensive instrument, but a very versatile and professional machine.

ARP introduced the world's first preset synthesiser, in 1972, closely followed by the Pro-Soloist, which was eventually to be redesigned and become the Pro/DGX. By a preset instrument I mean that all the controls for the VCOs, VCFs, and envelopes etc don't appear on the front panel. Instead there are rows of momentary switches that set each of the modules of the synthesiser to give a predetermined sound. The Pro/DGX, like most preset synthesisers, has the usual flute, clarinet, trumpet, string, cello, sax, vibes, piano, and banjo sounds, as well as a few of the gimmicky sounds with names such as 'razz' and 'telstar'. The sounds, which can be modified in various ways with the aid of the touch responsive keyboard, are all quite adequate, giving reasonable imitations of their respective instruments. The real problem with the Pro/DGX, however, is the momentary pushswitch selection of sounds. For most of the voicings, it's a simple matter of pushing the required button, but certain sounds are obtained by pressing two adjacent buttons at the same time, a process that needs a lot of care. The Pro/DGX then, is not one of ARP's best, but then there always has to be a runner-up.

The Omni-2 descends from two of ARP's earlier machines, the String Ensemble and the Explorer monophonic synthesiser, and really that is all the Omni is. The String section provides polyphonic violas, cellos and bass which can be balanced against a pseudo-polyphonic synthesiser section that has only one VCF and VCA, and independent bass section. The Synthesiser and String sections have separate envelope controls which enable the instrument to get a very full rich sound. Again, the styling of the new Omni-2 is awful, and though it has a few little extras such as the single/multiple trigger, I would go for an Omni-1 any day.

ARP's answer to guitar synthesisers is the Avatar, providing a means for your guitar to be interfaced with a box of tricks, much akin to an Odyssey without the keyboard. I don't intend to go into great detail about the Avatar as Paddy Kingsland did a very comprehensive review of the instrument in SI December '78. I find, however, that the instrument, though extremely versatile, requires a very clean playing technique. Whereas it is fine in a studio environment, I wouldn't like to try to control it under live conditions.

The Quadra is due for release within a couple of months; ARP are hoping it will consolidate the stronghold that the Omni has given them on the polyphonic synthesiser market. Consisting of four separate sections (bass; strings; poly/synth; and 2-voice touch-sensitive lead synthesiser), the Quadra also includes a new style voltage-controlled phase shifter. ARP also decided to incorporate an Arpeggiator (similar to the Roland JP-4's) to give sequencing effects. The Quadra is programmable, having eight factory-set patches and eight open positions. The factory presets can be erased for a total of 16 user-programmable positions. I shall be looking more closely at the Quadra in the near future.

These then are the current instruments on offer from ARP. There are one or two accessories available for use with these machines, the most interesting being the Sequencer — a 16-step analogue sequencer — and the Little Brother — an expander module giving an extra VCO when patched into a synthesiser.

A lot of thought goes into any new ARP product, and I think they will remain a force to be reckoned with in the field of mass-produced instruments. However, with so many other new instruments and ideas appearing almost every week, I feel that ARP could start to lose custom, especially from the professional end of the market.

Dave Crombie is an experienced electronic design engineer specialising in keyboard instruments.