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Alesis A6 Andromeda

16-Voice Analogue Synthesizer By Gordon Reid
Published April 2001

Alesis A6 Andromeda synthesizer keyboard.

Looking like a star cruiser, or something from the film 2001 (rather than just the year), Alesis' Andromeda is the first analogue polysynth that approaches the complexity of a digital workstation. But does analogue necessarily equate to quality?

If you're even vaguely interested in analogue synthesizers, you'll have encountered the hype surrounding the Andromeda. Indeed, the analogue-loving communities on the Internet have been buzzing about it non-stop for the year it has taken for the announcement to turn into reality. So here it is — the review of the first Alesis A6 Andromeda in the UK...

But First...

Let's get one thing out of the way before I begin. Despite Alesis' claims to the contrary, the Andromeda 16-Voice Real Analogue Synthesizer (as they call it) is not a real analogue synthesizer — at least, not completely. Huge chunks of its architecture are digital, and I'm not only referring to the digital effects, the microprocessor-controlled operating system, or even the memories. No... the controllers in the sound-generation system — the envelopes, the LFOs, and the Sample & Hold — are all digital, as is the oscillator tuning (although not the oscillators themselves). This makes the Andromeda a hybrid analogue/digital synth, much like, for example, the Sequential Prophet T8. However, the signal path is analogue. Alesis has even placed the digital effects section in a side chain. This means that, if you avoid these, the output from the Andromeda remains pure analogue, all the way from the oscillators to the outside world.

First Impressions

That dealt with, I'll start the review proper a few hours before the Andromeda reached my studio... in fact, I'll start with me trying to get it into my car. Since the boot was full, I had to put it in the front passenger seat. Well, either I'm getting old, or the thing in that box is one hell of a keyboard. At nearly 20kg, neither the Andromeda nor the remarkably sturdy box in which it arrives are for the faint (or weak)-hearted. For a synthesizer, it makes a pretty good Chieftain tank.

The military analogy doesn't stop there. Once on a stand, the Andromeda's silver-and-blue control panel assaults you. I've always liked blue synthesizers... my long-departed PPG 2.2 and the Supernova II will always have places in my heart. I like silver synths even more: the Korg Trinity, the Kawai K5000S, the Korg Z1... gorgeous! But what about a silver/blue hybrid? Unfortunately, my feeling is that the Andromeda's control panel was designed by a frustrated graphic artist who should get out of the house more often.

Getting the Andromeda up and running proved to be a doddle... simply a case of plugging the mains into the Andromeda's universal PSU, finding the Main outputs, and then trying a few patches. It sounds problem-free, and it was, but for the horrible noise that greeted me when I pressed a handful of notes. There's no doubt about it... the Andromeda is at heart an analogue synth, and this one was badly out of tune. Actually, the results were rather interesting, much like the Eastern tunings used by Wendy Carlos on Beauty In The Beast. But this was no time to be composing Indonesian music, so I pressed the Auto Tune button, and hoped that all would be well. Three and a half minutes later all was well. No glitches, no crashes, no nasty noises, no nothing... except for a perfectly tuned analogue polysynth.

The Andromeda offers a huge array of buttons and knobs, with a 640-by-240-pixel backlit LCD in the centre of the control panel. You can program sounds without referring to the screen, but you won't get far. This is because the physical controls call associated menus, and you then use the eight 'soft knobs' and 'soft buttons' located beneath the screen to edit the hundreds of parameters that comprise a patch. It sounds complex, but it isn't. For example, if you touch the Freq knob in the Filter 2 section, a screen appears. This displays six virtual faders and two selection menus controlled by the soft knobs, plus four 'page tabs' selected by the soft buttons. Turn a knob, and the associated virtual fader moves up and down, or the menu selection changes (as appropriate). Press a button, and a linked page within the Filter 2 section appears, complete with its virtual faders and menus.

In some situations, the screen appears jumpy, but this is a consequence of the sensitivity of the controls. Brush a knob lightly and the parameter value will jump to its current position, simultaneously updating the screen. You can get around this by placing the Andromeda in 'Pass Through' mode, which stops the knobs from sending a new value until you pass through the existing one.

As you delve deeper, you'll find that some programming sections have no top-panel knobs, and their buttons serve only to call the appropriate menus. To be honest, I never found this a problem because, like most players, I've become accustomed to this approach, where the most important parameters get a knob, and the rest live in menus. No problem.

Andromeda At A Glance


  • 32 (two per voice) with sub-oscillators plus hard and soft sync.
  • 16 ring modulators (one per Voice).
  • Noise generator.
  • Three audio inputs.


  • 32 resonant VCFs (two per voice).
  • Filter 1: two-pole multi-mode (low-pass, high-pass, band-pass, and band-reject).
  • Filter 2: four-pole low-pass.


  • Three LFOs per Voice.
  • One S&H generator per Voice.
  • Three multi-stage, multi-mode contour generators per Voice.
  • One multi-stage tracking generator per Voice.
  • Modulation matrix with 71 inputs and 92 outputs.


  • 61-note (C-to-C) velocity-, release velocity- and aftertouch-sensitive, semi-weighted keyboard.
  • Pitch and vibrato wheels.
  • Ribbon controller.
  • Five pedal inputs.


  • Analogue: distortion.
  • Digital: reverb, delay, chorus, flanging, pitch-shifting, rotary speaker.


  • Real-time arpeggiator (one per Voice).
  • 16-event, programmable step sequencer (one per Program).


  • 256 Programs in flash RAM.
  • 128 Programs in RAM.
  • 128 Mixes in flash RAM.
  • 128 Mixes in RAM.

The Analogue Bits: Oscillators & Filters

More than two years ago, Alesis decided to base the Andromeda's oscillators on the Moog 921b, as found in many Moog Modular synths from the '70s. They also looked to previous designs on which to base the Andromeda's filters — this time the the 12dB-per-octave Oberheim SEM multi-mode filter, and the 24dB-per-octave Moog 904a low-pass filter. Once they had identified these targets, Alesis' engineers built and tweaked their prototypes, and then passed the designs to the company's ASIC (Application-Specific Integrated Circuit) designers who shrank the circuits down on to two chips, the ASO and the ASF.

You may ask why Alesis chose to follow the current craze for all things Oberheim-ish and Moog-y. It might have been interesting to see what someone could make out of Emu oscillators, Polyfusion filters, or some of EMS's weird and wonderful designs. But Alesis clearly chose this path for market acceptability, and on this basis the choices are sound enough.

A6 Andromeda Oscillator controls.A6 Andromeda Oscillator controls.The dual VCOs per Voice (there are 16 voices, remember, so there are 32 oscillators in all) are provided by eight ASO chips. These offer all the usual analogue waveforms, the expected coarse and fine-tuning options, and a sub-oscillator one octave below the selected pitch. As well as providing both soft and hard sync, each oscillator can be frequency-modulated by the other (simultaneously if desired) and there are parameters for pitch envelopes, pulse-width modulation, plus a range of user-defined modulation sources and destinations. Each Voice also offers noise (in white, pink and red varieties) and a ring modulator. Again, there are many ways that you can modulate these sound sources, or use them as modulation sources (see 'Modulation Matrix' box, later).

Once you have determined the output created by each of the sound generators in a Voice, you mix them in the Pre-Filter Mixer. This allows you to balance the relative outputs of Osc1, Osc2, Osc1 (Sub), Osc2 (Sub), the noise source, and the ring modulator. However, you can also mix in a feedback loop taken from the post-filter signal. You might think that this would be asking for trouble, but it's nothing other than the old Minimoog trick of feeding one of the outputs back into the external signal input to fatten up the sound. Unfortunately, it doesn't have quite the same effect as on the Moog... results range from gentle tonal differences to buzzy overdrive. On occasion, the feedback even cancelled out some of the source. I think we should mark this 'shows potential'...

In contrast, I found the portamento particularly usable. It offers no fewer than nine different shapes, a legato mode (no portamento if you release the first key) and complementary staccato mode. This makes it capable of great expression, and it will imitate both the linear and exponential portamentos of various vintage synths.

Filter 1 is the two-pole resonant multi-mode filter that Alesis copied from the Oberheim SEM. It offers low-pass, high-pass, band-pass and band-reject modes. Filter 2 is the Moog-designed four-pole resonant low-pass filter, which will self-oscillate with the best of 'em, so you can use it as an extra audio source if you wish.

You can route the mixed oscillators' signals through these filters in four ways: through Filter 1 only, through Filter 2 only, through Filters 1 and 2 in series, and through Filters 1 & 2 in parallel. While less flexible than, say, the Waldorf Q's ability to send different oscillators down different routes, or its controllable and modulatable routings, the A6's architecture nonetheless offers a great deal of flexibility.

Thanks to Andromeda's comprehensive modulation matrix (of which more in a moment), you can modulate the filters themselves using a huge variety of sources. Things can get seriously weird if, for example, you modulate the cutoff frequency using the summed outputs of both oscillators as the source, then start adding envelopes, LFOs, and modulation depth controllers such as the Andromeda's mod wheels and ribbon controller.

The Digital Stuff: Envelopes, LFOs & Modulation

At this point, I can imagine some of you asking, 'Why did Alesis spend all this time developing an analogue mega-synth, only to ruin it with digital envelopes and LFOs?' Well, there's quite an assumption built into that question — that digital envelopes and LFOs are crap. This is a hangover from the early days of digitally controlled hybrid synths, whose over-stressed Z80s were incapable of generating fast envelopes while also calculating the LFOs and scanning the controls to see whether you had tweaked a knob. Today's processors are far more powerful, so the envelopes are faster, the LFOs are smoother, and the Andromeda feels and sounds far more 'analogue' than its predecessors. Indeed, the A6 updates all its digitally generated parameters every few hundred microseconds, and, despite smoothing transitions to remove quantisation noise, the fastest envelope response is still in the order of 1ms (one thousandth of a second). This is much faster than many other analogue synthesizers. It's also worth noting that the Andromeda's 16-bit parameter resolution allows you to be very precise in your choice of values. It's not unusual for there to be numerous stages between, say, 1.11 and 1.12 of a parameter, with a range of -100.00 to +100.00. This is a consequence of the fact that 16 bits offer 65,536 possible values.

One of Andromeda's envelope parameters shown in the LCD.One of Andromeda's envelope parameters shown in the LCD.Now, let's get down to the digital nitty-gritty. It's not just that the Andromeda's three envelope generators offer seven stages, nor that they're displayed graphically on the screen, nor even that you can direct them to almost anywhere within the Andromeda... no, I love the Andromeda's envelopes because they offer a choice of nine selectable slopes per stage. You really have to play with this feature to realise how good it is, and also just how much of the character of a favourite old synth is determined by the responses of its envelopes. Biting attacks, smooth attacks, squelchy attacks, natural decays, aggressive decays... they're all there if you care to experiment. Furthermore, you can loop the envelopes using any stage as the start point, and any later stage as the end-point, and you can choose to smooth (or not) the contours thus generated. This is excellent for slow, evolving pads. Then there are the multiple keyboard trigger modes, the triggering capabilities provided by the modulation matrix, the interactions with the LFOs, sequencer and arpeggiator... far too much to cover here, I'm afraid.

The Andromeda offers three LFOs, plus Sample & Hold, per Voice. The LFOs offer six waveforms with waveshaping of the square wave and saw/triangle/ramp waveforms. There's a slewed Delay function (up to 131 seconds before full amplitude is reached!) and you can program the LFOs to run freely, sync them with key-presses, and even determine their start phases. The LFOs also offer variable offsets, so that you can use them as positive modulations (like a guitarist's vibrato), bi‑polar modulations (the vintage synth approach), negative modulations, or anywhere in between. You can even ask them to clip at their extremes, and modulate all their major parameters using the modulation matrix. The only unexpected limitation is the maximum LFO speed. At just 25Hz, it's simply not fast enough for some applications. Alesis have undertaken to increase the maximum to 50Hz, but have also conceded that it may not be possible due to microprocessor limitations.

Envelope 2 hardware controls.Envelope 2 hardware controls.

Now, having mentioned it numerous times already, it's time to explain the modulation matrix itself. This is a software matrix of 71 sources and 92 destinations. Some of the modulations — the ones you would expect to find hard-wired on any well-endowed vintage polysynth — have dedicated top-panel controls. If you touch one of these, an appropriate screen appears, and you can select a source and amount to control it. For the others, you enter a page that allows you to determine all the routings and modulation amplitudes. This is useful for finding (and turning off) stray modulations that creep in when editing sounds. Multiple sources can drive a single destination simultaneously (the sources are summed), and a single source can drive multiple destinations. What's more, if you want more modulation from any given source, you can use two routes and double the effect. Very nice.

I should also mention the Andromeda's 'Tracking Generator' (TGEN). This allows you to redefine the input and output relationships of the modulation sources. A simple example of this is the relationship between key velocity and signal amplitude. Instead of living with the normal 'double the velocity, double the gain' relationship, you can draw your own curves, even creating dips or peaks in the response if you wish. This is a superb but esoteric facility, and I can't see people using it much. Nevertheless, given the amount of talk that has focused on its analogue qualities, it's ironic that the Andromeda is at its most impressive when it's at its most digital.

Effects & Mix Mode

The Andromeda's effects are split into two camps: analogue distortion and twenty-eight digital algorithms and combinations (choruses, reverbs, delays and so on). Both of these are mixed with the source signal (if present) at the Main outputs.

Alesis A6 Andromeda DFX shown in the LCD.The analogue distortion is created by a transistor circuit with four levels of drive: Easy, Light, Heavy, and Killer. There are three destinations: the Main outputs, 'Digital Effects (left)' and 'Digital Effects (right)'. I found it useful for adding grit and drive to some patches, but I'm old enough to be rather fond of valves, and I find transistor distortion harsh and edgy. Perhaps if Alesis had added a low-pass filter or an EQ to this buss it would be better, but without these, I think it sounds like a cheap stomp-box.

In contrast, the digital effects — based on a cut-down version of the Alesis Wedge — are first-class, with enough configurations and parameters to keep you busy for quite a while. My only reservation here is the so-called Lezlie effect (Alesis' spelling, not mine). I find this ghastly, and think it made the Andromeda useless at any form of Hammond imitation.

Alesis A6 Andromeda Effects send levels shown in the LCD.The maximum number of simultaneous digital effects is three (in series), but the configurations also include parallel pairs. With the effects blocks, routings and parameters displayed on the LCD, you'll be flying around this section in no time at all. I suppose it should be no surprise that Alesis can program an excellent digital effects section, but I find it ironic that — yet again — the Andromeda is at its best when it's at its most digital! However, here's the sucker punch...

An Andromeda 'Mix' is the same thing as a Korg Combi, a Kawai Multi or a Roland Performance. You use it to layer up to 16 Programs, create keyboard splits with up to 16 regions, or create 16-part multitimbral setups with (if you wish) a different Program responding to each incoming MIDI channel. You can even edit the contained Programs while in a Mix, because Mixes have a useful 16-Program buffer space that does not update or damage the original, saved patches. However... there is only one set of effects in the Andromeda, so you can not allocate different effects to the Programs in a Mix. This means that, unlike the Korg Trinity and Triton or the Novation Supernova, the Programs can not import their associated effects; you can only adjust their Send levels and pans. This might have been state of the art 10 years ago, but today it's most certainly not.

Ins & Outs

The back panel of the Andromeda is resplendent with inputs and outputs. Firstly, there are the Main stereo outputs. These carry the signal and any effects that you program into your sounds. If you want, you can remove the dry Program from these, so that you hear only the 'wet' signal, which can be useful for sound effects and such like. Alongside the main outs, you'll find the Auxiliary stereo outputs, which you can use as a second stereo pair (minus effects) or as two monophonic outputs.

Alesis A6 Andromeda rear panel.Alesis A6 Andromeda rear panel connections.

The eight stereo sockets that comprise the 16 Individual Voice outputs are an impressive sight, but I'm not sure how useful they will be. I've long campaigned for individual Program/Buss outputs on workstations, but Alesis have instead chosen to give each Voice its own output. You can use 'Mono' mode to select which Voices will be used by any given Program, so, if you disable the Program on the Main and Aux outputs, you'll at least know which Individual Voice output(s) will carry the sound. But it's not quite what I wanted, because you then need to sub-mix these outputs before your main desk. Furthermore, the A6's limited effects structure means that you need a rackful of external processors if you want to treat each Program individually within the final mix. Compare this to (say) the truly multitimbral effects and output busses of the aforementioned Supernova II, and the Andromeda looks a little sad.

There are two CV inputs, one for the oscillators, and one for the cutoff frequencies of the filters. CV-controllable attributes within the oscillator section include the frequency, the pulse width, and the amplitudes of the FM paths between the oscillators. I found these inputs extremely sensitive, far more so than 1 Volt-per-octave, so I couldn't play the Andromeda from my Analogue Systems Sorceror. It's also too sensitive for use with conventional analogue sequencers unless you scale the inputs (something else you can do in Mono mode). The positive side to this is that small voltages can make drastic changes to your sounds should you wish.

The three audio inputs allow you to process external audio through the Andromeda's filters, VCAs and effects units. Firstly, you can process audio through the signal paths of Voices 15 and 16, either as a stereo pair, or as two independent monophonic sources (this disables the oscillators for these voices). Alternatively, you can use the 'V 1-16' input, at which point the external audio replaces the internal noise source, and becomes available alongside the internal oscillators for all 16 Voices.

Seven further holes on the rear panel offer three pedal inputs (one for sustain, one for momentary switches, plus a continuous controller, all programmable within the modulation matrix), the ubiquitous MIDI In/Out/Thru and, finally, a stereo headphones output.

MIDI Matters

Andromeda's ribbon controller strip.Andromeda's ribbon controller strip.The Andromeda has a merely competent MIDI specification. At the time of writing it lacks MIDI Clock Out, and lacks SysEx transmission and reception of the control panel knobs and buttons. This makes it unsuitable for use as a master keyboard when using the arpeggiator or sequencer, and unable to control other synth's parameters. Apparently, these omissions are on Alesis' immediate wish-list of updates but, to quote one of the company's engineers, 'these are planned, but the standard disclaimer applies'.

On the positive side, you can use the Andromeda as a conventional master keyboard, with transmission and reception of controller messages such as mod wheel, aftertouch and so on. Furthermore, you can select the MIDI Continuous Controller associated with each of its controllers, the foot pedals, and the ribbon controller.

Finally, the SysEx implementation allows you to dump and load Programs and Mixes to the User areas, but you cannot write to the Preset banks using SysEx.

Sounds & Programming

I have to admit that I'm not a fan of the A6's factory sounds. With the exception of a few Programs in Preset Bank 2, I found every one of them big, fat, lumpy, and virtually unusable in a mix. As far as I can tell, they're designed to capture people's attention when they press one note in the middle of a music store. Of course, there's nothing wrong with this; it's important to turn heads when you're in a competitive market place. But it makes it harder for the passer-by to assess the true potential of the instrument in a short time... it might take weeks to create a balanced set of sounds that would make use of the Andromeda's full range.

Fortunately, Alesis are still creating factory sound sets. Furthermore, they plan to archive the new and existing banks on their web site, so you should have immediate access to this growing library. I, however, needed to put Andromeda to the test, so I settled down to some programming.

I started with my favourite ARP monophonic brass patch. Removing unwanted facilities such as the multi-stage envelopes and overly complex modulation routings, I set about recreating this simple sound. It was at this point that I realised how much I liked the control panel. OK, I still wasn't sure about the graphic design, but the functionality is first class; it didn't take long to get the sound I wanted (particularly helpful was the fact that if you press the 'Up' and 'Down' buttons simultaneously, you jump to the most useful value of any given parameter, and can tweak from there). Next, I opened the filter a little, reduced the envelope following, and obtained the result I anticipated — a monosynth flute. As I continued, I noticed something about the Andromeda. Much like a Minimoog, it's really easy to get good sounds out of it. Indeed, I found that many of these simpler sounds were the best. Forget the sub-oscillators and the ring mod, use one filter, program simple, snappy envelopes, and add just a hint of reverb... you'll hit pay-dirt nearly every time.

Alesis have admitted that their ASICs do not sound identical to the Moog oscillators, nor to the Moog and SEM filters that they copied. I'm not surprised... it would be remarkable if something crafted in micrograms and micrometers sounded the same as many square inches of vintage circuitry. Tonally, I found it to be more like an ARP than a Moog, but that's no criticism — I was using Odysseys for bass and Pro-Soloists for leads long before I bought my first Moog. In the past, some manufacturers have added powerful (but hidden) bass boosts to their digitally controlled analogue synths to 'warm up' the sounds, and if you're after Moog-y sounds, the Andromeda would benefit from this. But if I want to add EQ, there are better ways to do this, and without compromising the synthesizer itself.

While programming away, I found the Unison facility particularly useful. It allows you to select how many voices you want under each key, both in monophonic and polyphonic modes. Once you've done this, you can spread the voices around the central pitch to create truly huge sounds. If you use this judiciously, it's superb — a passport to Memorymoog territory. Another option I tried was Stack. In polyphonic mode, this allocates all the Voices to the keys that you're playing. So, if you press just one note, you get a speaker-shattering 16 Voices under that key. If you press two notes, the Andromeda allocates eight Voices per key, three notes get five Voices each... and so on. I didn't find this particularly useful, because there were too many occasions when it made the Andromeda sound out of control. If Alesis were to place an upper limit on the number of Voices per key, I could see myself using this feature much more.

The Andromeda has another neat trick up its sleeve, derived from the Yamaha CS-series of the mid-'70s to early '80s. In the Post-Filter Mixer you can add back the unfiltered sine waves generated by Osc1 and/or Osc2, and/or the output from the ring modulator. This allows you, for example, to reinforce the fundamentals of otherwise heavily filtered sounds.

Despite this (rare) Japanese influence, the Andromeda falls squarely into the 'American' synthesizer camp, and it excels at brass, strings, and huge pads. This shouldn't be surprising... those are the strengths of all the classic analogue polysynths from the Prophet 5, Oberheim OBX and Memorymoog onwards. The A6 is also well suited to recreating the complex, evolving sounds of the Matrix 12. But there are other areas where, for me, it doesn't shine at all. Most obvious of these are the organs. I'm no slouch at getting an organ out of a synth, but the Andromeda proved to be extremely reluctant (I'm being polite!). Also, the Andromeda refuses to go where no other analogue synth has gone before: acoustic pianos.

In contrast, it is first-class at Rhodes, Wurlitzer, and FM piano patches. It can be difficult to program these on some analogue synthesizers, but the Andromeda produced them with consummate ease. Ironically, once again it's the almost 'digital' clarity of its oscillators and filters and the speed of its envelopes that make this possible. Just use the programming principles of the classic Roland electric piano (oscillators sync'ed 21.5 semitones apart, with appropriate filter and envelope settings) and you'll hear what the JXs were trying to produce. OK... so it can sound like a Japanese synth, too!

The Clock Section: Arpeggiator & Sequencer

You'll find the Andromeda's arpeggiator, sequencer, and various sync capabilities grouped together in the Clock Section. There are three clocks available: MIDI Clock, the internal Master clock (which can itself be slaved to incoming MIDI), or the Local clock for the given sequence, arpeggio, or modulator.

The arpeggiator offers a very limited number of modes compared to most modern arpeggiators (just four!), and it lacks a Random mode. I also didn't find the arpeggiator control menus particularly intuitive, and I would have appreciated some physical controls on the top panel: buttons for mode, local rate, and latch would be a huge improvement.

The sequencer is more complex, but no harder to use. A set of pages represent the 16 steps, and this is where you enter the note values, note velocities, whether there are any rests... and so on. Sadly, you can only create these sequences by programming them, because there is no facility to play them into the system. But not all is gloomy... every Program has an associated sequence which is stored as part of the Program itself. In Mix mode, you can therefore have 16 different arpeggiated Programs playing 16 different, dedicated sequences, all sync'ed to a single Master clock. Furthermore, you can specify different relationships to the clock for each of these, creating some very complex effects indeed. It's a Teutonic dream. Alternatively, you can have each running at its own tempo, perhaps with no musical relationship to the others. Yurgh!

However, there's one important omission to mention: the Andromeda will synchronise to the absolute timing of external devices, but it has no idea about bar-lines. This means that your sequences can be in time, but out of musical synchronisation, with other instruments. This will be very frustrating for 'groove' DJs.

Other Issues

I'm well aware that some purchasers will use the Andromeda as a sophisticated source of sound effects, arpeggios and sequences, and rarely play it conventionally. But that's not my way... if something looks like a musical instrument and sounds like a musical instrument, I want to be able to play it like a musical instrument. So here's a disappointment... there is only one version of Andromeda, with just 61 keys. I'm a 76-note sort of bloke, and I would be keen to see a 'Pro' version sometime soon. On the bright side, the plastic, semi-weighted keyboard is pleasant and responsive. When the programmable sensitivity curves for velocity, release velocity, and channel aftertouch become available in a future OS revision, it will be even better.

Other features missing from the current OS include the Manual function (which resets the sound in the edit buffer to the positions of the knobs and buttons on the control panel) and the Chord memory function. At the time of writing, a new OS, with these functions enabled, is at the beta-test stage.

Andromeda A6 pitch bend and modulation wheels.Andromeda A6 pitch bend and modulation wheels.Apart from the pedal controller inputs, the Andromeda offers three major performance controls. To the left of the keyboard, you'll find the standard pitch-bend and modulation wheels, both of which you can assign to any destination within the modulation matrix. The third is the long and desirable ribbon controller whose function, again, you can assign within the mod matrix. Indeed, you can assign it to multiple destinations with differing amounts if you wish, and — because it is monitored from both ends simultaneously — you can even split it to offer two different functions in different positions. I understand that new ribbon modes are promised for the future — track and hold, relative, absolute — but, as always, don't bank on these appearing until they appear (if you see what I mean).

Before concluding this review, I would like to put a flea in Alesis' ear about a couple of other deficiencies. For example, it's far too easy to get the signal path to clip and distort. You need to reduce the levels in both the pre-filter mixer and post-filter mixer to avoid this, because it will otherwise ruin your sounds. I would also like to see more flexibility in Voice panning. A number of vintage synths — the Oberheim OB8, the Sequential Prophet VS, and others — allow you to position each voice within the stereo field. The only way to do this on the Andromeda is to use the individual outputs and 16 channels on your external mixer!

As for bugs? Oh heck... the ones I noticed were so minor that I'm not even going to mention them. But I do have one misgiving that I must share with you. Some cheaper Alesis products have stood the test of time poorly. The 1622 mixer is perhaps the most famous example of this, but the knobs and screens on some other products have also failed with disturbing regularity. As for the early ADATs... these represented a price/performance revolution, but the word 'reliability' did not seem to be in their specification. I think it's right to offer Alesis the benefit of the doubt, and not once did the Andromeda give me cause for concern — but I have been burned before. Let's face it, the Andromeda has a lot of knobs and buttons, so I'll be keeping my fingers crossed.


That the Andromeda is a powerful, meaty synth is obvious. Indeed, I suspect that it's the closest thing there's ever been to an analogue workstation. But most people who love it will do so for its 'American' sound which can range from warm to harsh, fat to thin, squelchy to digital, as you desire. Alesis' ASIC technology has produced an instrument with its own character, and that's no bad thing at all.

In that light, the Andromeda earns a significant 'thumbs-up'. It's all-but complete, it didn't crash once, and it sounds great. On that basis, you should certainly try it. But a word of warning... don't base your views on the factory sounds. Delve deeper, and don't stop at a bit of gratuitous knob twiddling on the control panel. Get into those menus.

As you will have realised, I like the Andromeda a lot. This wasn't entirely the case at first, yet the more I experimented with it, the closer friends we became. But, ultimately, it's not for everyone. Its price alone determines this and, for me, arguments that it's equivalent to 16 monosynths for less than £200 each do not wash. Let's face it... the majority of players want digital workstations with all the facilities of the Andromeda — and more — but at a fraction of the price. So Alesis must be keeping their fingers crossed that the Andromeda will attract enough people to justify the time, effort and cost expended in its development. I hope that it does, because the company should be congratulated for stepping beyond the self-imposed boundaries of other synth manufacturers.


It's no secret that analogue synthesizers tuned too precisely lose some of their warmth, and this is why some analogue purists decry digitally controlled oscillators — they're simply too in tune. To overcome this, the Andromeda's OS allows you to tune individual sections such as the filters and the VCAs, but leave the oscillators free to drift a little. Sure, there's a background tuning function that continuously re-tunes voices that are not in use, but if you want your oscillators to drift, you can turn this off. Whether this makes the Andromeda 'warmer' is, I suppose, a matter of taste. As for me, after the initial tuning, I couldn't hear any difference either way.

Modulation Matrix

The Andromeda manual lists the following 71 modulation sources. Unfortunately, it does not list the 92 destinations, and I'm not going to try to find them all for you!

  • Offset (a value).
  • Voice Key Number — voice-specific note.
  • Voice Key On Velocity.
  • Voice Key Off Velocity.
  • Key Aftertouch.
  • MIDI Aftertouch — from MIDI IN.
  • Modulation Wheel.
  • Pitch-bend Wheel.
  • Ribbon Value — in whole mode.
  • Ribbon Left — from left side only.
  • Ribbon Right — from right side only.
  • LFO 1.
  • LFO 2.
  • LFO 3.
  • Sample & Hold Level.
  • Envelope 1.
  • Envelope 2.
  • Envelope 3.
  • Track Gen Step — the quantised output of the tracking generator.
  • Track Gen Level.
  • Sequencer Level A — output of the sequencer's Note level.
  • Sequencer Level B — output of the sequencer's Velocity level.
  • Sequencer Level C — output of the sequencer's Gate level.
  • Arpeggiator Key Number — arpeggiator-generated Note level.
  • Arpeggiator Velocity.
  • Portamento Level.
  • Portamento Raw Level.
  • Voice Random — a note value picked at random from those being played.
  • Sustain.
  • Foot Switch.
  • Control Pedal.
  • MIDI Volume.
  • Program Key Number.
  • Key Trig Rate.
  • Program Key On Velocity.
  • Program Key Off Velocity.
  • Program Key Down.
  • Program Number of Keys On.
  • Tempo.
  • Master Clock (on board).
  • MIDI Clock.
  • MIDI Start.
  • MIDI Stop.
  • MIDI First Clock.
  • MIDI Start/Continue.
  • Sample & Hold Clock.
  • Program Key Trigger.
  • External Trigger 1.
  • External Trigger 2.
  • Global Random.
  • Envelope 1 Attack.
  • Envelope 1 Decay 1.
  • Envelope 1 Decay 2.
  • Envelope 1 Sustain.
  • Envelope 1 Release 1.
  • Envelope 1 Release 2.
  • Envelope 1 End.
  • Envelope 2 Attack.
  • Envelope 2 Decay 1.
  • Envelope 2 Decay 2.
  • Envelope 2 Sustain.
  • Envelope 2 Release 1.
  • Envelope 2 Release 2.
  • Envelope 2 End.
  • Envelope 3 Attack.
  • Envelope 3 Decay 1.
  • Envelope 3 Decay 2.
  • Envelope 3 Sustain.
  • Envelope 3 Release 1.
  • Envelope 3 Release 2.
  • Envelope 3 End.
  • MIDI Continuous Controller A.
  • MIDI Continuous Controller B.
  • MIDI Continuous Controller C.
  • MIDI Continuous Controller D.
  • MIDI Continuous Controller E.
  • MIDI Continuous Controller F.
  • MIDI Continuous Controller G.
  • MIDI Continuous Controller H.

What's In A Name?

There's been a lot of speculation regarding the Andromeda's name. Is it the A6, or is it the Andromeda? Here's the whole, sad tale...

Recent Alesis keyboard synths have borne a number that refers to the number of keys on the keyboard. Those with 61 keys have a 6 in the name, those with 76 keys have a 7, and those with 88 keys have an 8. It was logical, therefore, that the Andromeda would start life as a 'Something 6'. The engineers liked the idea of using the letter 'A' for analogue, so they ended up calling it the A6.

However, the then-marketing manager of Alesis' synth division (who has since departed) apparently thought that A6 was too impersonal. He also worried that the '6' might mislead players brought up on the Prophet 5 (five voices), the Jupiter 8 (eight voices) and so on. Apparently, he then spent two years trying to think of names. The first of these was 'Velociraptor'. No one liked that... Likewise 'Vogue' (suggested by an Alesis salesman because it rhymes with Moog). Better suggestions included 'Monolith' (with its Arthur C Clarke connotations), and 'Prologue' (Professional Analogue). However, eventually 'Andromeda' (from The Andromeda Strain, a '70s sci-fi movie) struck the right chord, apparently. Female, astronomical, and a disease, all rolled into one.

An attempt was then made to sell this name to the rest of Alesis, but some of the engineers resisted, because they thought that the similarity between the name of the ASIC chips at the heart of the synth and the sound of 'A6' was really funny. Anyway, the President of Alesis was not prepared to adopt either name wholeheartedly, so — citing the Roland JP8/Jupiter 8 as an example — they settled for a compromise.

And that's why it's called the Alesis A6 Andromeda.


Despite (or perhaps because of) its large number of parameters, the Andromeda has only a moderate storage capacity. There are three banks of 128 Programs (called Preset 1, Preset 2, and User) plus two banks of Mixes (Preset 1 and User). You can save your own creations in the User banks, but 256 patch memories are far from generous, so Alesis has added a slot for PCMCIA S-RAM cards. Each 512K card can hold two banks, and larger cards should be able to hold proportionally more.

The Preset banks are stored in flash RAM, so you can also overwrite these, but you must do so in complete banks rather than one Program or Mix at a time. Simply compile the bank in User memory or on a PCMCIA card, and then dump it in one swoop. Of course, you have to be careful that you don't knobble the relationships between your Programs and Mixes, but that's a common failing of analogue synths from the bi‑timbral JX10 onwards.

To Rack, Or Not To Rack...?

You may already be wondering whether Alesis will release a rackmount Andromeda. After all, studio and stage space is often at a premium. Furthermore, the Andromeda is no lightweight, and most people would prefer to hump a few 'U' of rack equipment rather than an Anvil case weighing the best part of 50kg. On the other hand, the Andromeda's control surface is a large part of its character, and its screen requires space that might be difficult to accommodate in a rack. Then there's the ribbon controller... what would you do with that?

I suspect that Alesis will eventually make a rack module incorporating Andromeda technology, but it will require a number of compromises with respect to the keyboard. I also think it will be quite a long wait.

Andromeda's Factory Sounds

If you insist on wandering into your local music emporium and testing the factory sounds, you'll find them organised into rough groups, as follows (although these are my definitions, not Alesis'). Mind you, whether these groups will survive the next round of upgrades is anybody's guess.

0 Unison sounds Dance Mixes
1 'Clocked' sounds (not arpeggiated) Dance Mixes
2 Miscellaneous analogue sounds Dance Mixes
3 More miscellaneous analogue sounds Dance Mixes
4 Mostly big pads Dance Mixes
5 Filter Sweeps Dance Mixes
6 Mostly pitched, percussive sounds Dance Mixes
7 Miscellaneous analogue sounds & effects Bass/Lead & Pad/Lead splits
8 More percussive sounds Bass/Pad & Bass/ Accompaniment splits
9 Imitations of vintage synths Bass/Instrument splits
10 Sound effects Huge, layered pads
11 Sound effects Layered lead synths
12 External audio processing Programs Dance Mixes
0 Sequenced Programs Empty
1 Sequenced Programs Empty
2 Sequenced Programs Empty
3 Sequenced Programs Empty
4 Sequenced Programs Empty
5 Sequenced Programs Empty
6 Arpeggiated Programs Empty
7 Arpeggiated Programs Empty
8 Sequenced analogue drum Programs Empty
9 Sequenced analogue drum Programs Empty
10 Sequenced & static analogue drum Programs Empty
11 Sequenced analogue drum Programs Empty
12 Sequenced & arpeggiated analogue drum Programs Empty
0 Miscellaneous analogue sounds (no Mixes in Bank 2)
1 Basses
2 Basses
3 Pads
4 Pads
5 More miscellaneous analogue sounds
6 Strings
7 Brass
8 Analogue attempts at acoustic sounds
9 More analogue attempts at acoustic sounds
10 Lead synth programs
11 Lead synth programs
12 More sound effects


  • The range and quality of its sound.
  • Uniquely flexible envelopes.
  • The carefully designed OS.
  • Unending modulation possibilities.
  • The control panel (some people are going to love it).


  • Monotimbral effects.
  • 'We're working on it' omissions (such as the limited MIDI spec).
  • It's not cheap.
  • The control panel (some people are going to hate it).
  • Of course, it isn't discrete components. They sound much better (no, I'm joking!).


The Andromeda is unique. There's currently no other powerful, keyboard-based, multitimbral synth with an analogue signal path, so it's going to carve a niche for itself. With a combination of excellent facilities and the occasional surprising deficiency, it also has a distinctive character of its own. And it sounds a treat. If only analogue technology was, say, 50 percent cheaper?


£2599 including VAT.

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