The ARP Odyssey was a fabulous and innovative synth that has an interesting history.

Moog started off with their modular synths... so did ARP, firstly in the form of their 2500 and then the more affordable and portable 2600.

Moog then released the MiniMoog, the world's first totally pre-patched synth that didn't require patch cords. And it was portable. It was, of course, an immediate success with keyboard players the world over and whilst the 2600 was relatively portable, the MiniMoog was even more so.

ARP retaliated with the Odyssey in 1972.

The Odyssey was clearly derived from the 2600 and had two audio oscillators, a white/pink noise generator, a ring modulator, a resonant lowpass filter, a (non-resonant) highpass filter, an AR and an ADSR envelope, an LFO and a very flexible sample+hold unit which, more than anything, proved the Odyssey's modular heritage. Already, you can see that the specs on paper alone are superior to the MiniMoog's.

But there were other, more subtle functions on the Odyssey that were lacking on the MiniMoog.... pulse width modulation (PWM), oscillator sync, envelope 'repeat' (triggered from the LFO) and comprehensive modulation facilities where (almost) anything could be routed to (almost) anything with (almost) the same flexibility as a true modular synth. The Odyssey was also a lot more stable - in fact, the whole ARP range was famed for better oscillators - and you could guarantee that, once warmed up, the thing would stay in tune for your gig, a feat that filled MiniMoog owners with envy!!

The Odyssey had another trick up its sleeve however.... it was 'duophonic'.... sort of! It was possible to play each of the two oscillators independently allowing you to play two notes at a time. Two notes!!!? This was unheard of and was a revolutionary new feature! Of course, because both oscillators shared a single filter and envelope, the results were compromised but at the time, this was quite a unique selling point and many used it to good effect in performance. On paper then, the feature set of the Odyssey left the poor old MiniMoog standing... more 'modules', more sound shaping facilities than you could shake a stick at, 'duophony', stability and more.... the MiniMoog didn't have a chance..... or so you would have thought.

What the Odyssey lacked, however, were the MiniMoog's unique pitchbend and mod wheels. Instead, it had this crappy little rotary knob for pitchbend and you had to use the modulation sliders below the oscillators to introduce vibrato - quite a tricky manoeuvre! The pitchbend knob wasn't totally unusable - it had a 'dead area' at its centre position so that bend could be controlled with more subtlety - and many such as George Duke mastered it to good effect. However, it just didn't work as well or as intuitively as Moog's wheel.

And then there was 'the sound'.

Many say that the MiniMoog had a 'fatter' sound because of its third oscillator. This is largely tosh - Oscillator 3 on the MiniMoog was mostly used as an LFO for vibrato in 99% of its sounds rendering it essentially a two oscillator synth just like the Odyssey most of the time. No - the difference in sound between the two lay in their filters. Whereas the Mini had the famous 24dB/Octave Moog 'ladder' filter, the Odyssey had a more 'polite' 12dB/Octave lowpass filter of ARP's own design. But it is here that the story gets blurred as some claim that the original white Odysseys shipped with a beefy 24dB/Octave 'Moog' filter clone.

You see, ARP had pretty much copied the famous Moog 'ladder' filter in their ARP4035 filter design and this was used in early versions of the the company's 2600 modular synth. Robert Moog was understandably less than happy about this copyright infringement and so pursued ARP to cease using his patented design. ARP were forced to concede and so designed a new, proprietary filter. This was the ARP4023, a 2-pole, 12dB/Octave lowpass filter and it was this that was was used in the original white Odysseys, not ARP's Moog clone. However, the story doesn't quite end there....

In 1974, the Odyssey had a face-lift in the form of the new black and gold Mk2. Between 1974 and 1975, the new Mk2 used the same 2-pole 4023 filter from the white Odyssey but between 1975 and 1976, the Mk2 Odyssey was mysteriously shipped with the ARP4035 Moog filter clone inside! Quite how or why this happened is unknown but it is possibly this that gives rise to the confusion (and rumours) regarding the relationship between the Odyssey and the Moog filter.

If the early Odysseys had a weakness, it was the 4023 12dB/Octave filter. Being 2-pole, it lacked the 'punch' of the Moog's 4-pole filter. Also, the 4023 was quite noisy. On the positive side, however, high resonance settings on this filter didn't attenuate low frequencies as was the case on the Moog and and this made it ideal for synth bass sounds. Also, with a shallower cutoff slope, it could be argued that the Odyssey had a brighter sound overall. Quite why ARP chose to go with a 2-pole design, however, is anyone's guess - perhaps it was to give the Odyssey a different sonic identity to the MiniMoog... perhaps it was to distance themselves even further from the Moog filter debacle. Who knows!

But the story of ARP, the Odyssey and their filters doesn't end there!

ARP had developed their own 4-pole 24dB/Octave filter, the ARP4072, that was intended for the Mk2 Odysseys (and other ARP products). But there was a bit of a problem....

Someone at ARP had miscalculated the component values in this new filter and, as a result, its frequency response only extended to a mere 12kHz!! It seems that this filter made its way into some production runs of the 2600 before the problem was spotted. The problem wasn't insurmountable - owners of those synths could have this limitation fixed by having four resistors changed - but it must have been extremely embarrassing for this eminent synth manufacturer.

The problem was finally rectified once and for all in yet another filter design, the ARP4075, and it was this filter that was used on all subsequent Odysseys (and other ARP products) after 1976.

The Mk2 (right) was a very classy looking instrument with gold labelling on a textured black panel. The colour coded 'match-head' slider caps were retained from the previous white-faced model and it was functionally identical (even down to that crappy pitch bend knob!).

Significantly, the Mk2 added CV and gate inputs and outputs on the rear panel for interfacing with other ARP synths and, indeed, ARP's own sequencer and other ARP products such the quirky 'Little Brother' oscillator expander module.

So, endowed with a new 4-pole filter and new interface possibilities, the new, black+gold Odyssey Mk2 went on to enjoy enormous success with a wide range of musicians at the time. The new Odyssey with the 4075 filter had its own sound that was cleaner and less 'coloured' than the MiiMoog.

But that's not to say that the Odyssey lacked character - far from it! At lower resonance settings, the Odyssey sounded equally as beefy and punchy as a MiniMoog but the new 4075 filter offered far greater stability at high resonance settings. The downside to the design was that it didn't sound so good when overdriven. But to say that the MiniMoog or the Odyssey was better or worse than the other would be missing the point - both had their strengths and weaknesses and to compare the two would be like comparing a Les Paul with a Fender Strat.

However, whilst the Odyssey was altogether a far more versatile synth than the MiniMoog in almost all respects, the MiniMoog had a reputation for being more 'playable' and more 'expressive' with its performance wheels. ARP were well aware of this but could not be seen to copy Moog (again!) and so they devised a new performance mechanism which they called "Proportional Pitch Control" (or PPC).

Three white pads replaced the pitch bend knob. The left pad provided downwards pitchbend and the right one did upwards pitch bend whilst the middle one controlled vibrato. The pads were pressure sensitive so that the harder you pressed them, the more effect you would get.

PPC wasn't a bad system actually - not as 'natural' as the Moog's wheels but certainly a marked improvement on the old rotary knob and they made the Odyssey a far more expressive and playable synth.

The Odyssey was now probably at its zenith - it looked great, it sounded great and the PPC pads gave it an expressive voice. However, if the black-faced Mk2 Odyssey was a class act, things were soon to change when ARP dramatically overhauled their cosmetic design.

For some reason, ARP switched from the tasteful black and gold facia in 1978 to a new black and orange colour scheme for all their products. Whether you like or hate this colour scheme is irrelevant - the fact is that it was a bad design!

As you can see from the Mk3 photo (right), the keyboard protruded over the edge of the casework making it very easy to break the keys especially when in transit. Also, the composition of the new slider caps was incorrectly formulated and they cracked (and fell off) with even moderate use! As a result, any Odysseys you might see now from this era will almost invariably have broken or cracked keyboards and no slider caps!

Furthermore, some bright spark at ARP thought that it would be a good idea to use what appeared to be linoleum floor covering as end-cheeks for this new Mk3 design! This flimsy material marked very easily (you could damage it with your fingernail!!) and these new models soon looked tatty even on display in music stores. The new cosmetic design may have been bold... it may have been 'modern' - futuristic even - but it was totally impractical for the average gigging musician!

Despite these cosmetic problems, the Odyssey still continued to sell but not in the quantities it had enjoyed in the past. ARP's market was dwindling under the onslaught of cheaper (but capable) synths from Roland, Yamaha and Korg as well as new models from old rivals Moog and whilst the competition were introducing new synths with ever more features and functionality, ARP were pretty much standing still. Innovation seemed to have completely ceased at ARP and they were simply repackaging exisiting products in different guises, most notably in the ill-fated ARP Avatar guitar synth in 1977. Essentially an Odyssey with a special pickup and pitch-cv convertor, the Avatar had cost so much to develop, it almost single-handedly brought the company to its knees.

Then in 1978, a man named Dave Smith was to change everything with his programmable, polyphonic Prophet 5.

ARP responded with the polyphonic QUADRA (another repackaging job, this time of the OMNI II) but it was too late and the company was in trouble. Over the years, ARP had enjoyed a huge turnover and had managed to secure a large percentage of the synth market at the time but they had made little or no profit. Combine this with internal management conflicts, ill-conceived products, bizarre R+D plans and an ever-diminishing market share, ARP were not to last very long. In fact, they finally went to the wall in 1981.

But the fact remains that the ARP Odyssey was undeniably a fantastic synth and one that deserves the title of 'classic vintage'. It was capable of a far greater pallette of sounds than the MiniMoog (and also many other synths of the era) and although the sound of the Odyssey wasn't quite as characteristic as the MiniMoog, it was actually better at creating certain sounds, especially 'imitative' sounds for which Moog products were sometimes too 'coloured'.