Alesis Ion

Alesis Ion Image

The Ion Analog Modeling Synthesizer is one fat-sounding digital synth! Using Alesis' proprietary DSP Analog Modeling technology with a 500 MIPS processor (500 million instructions per second), every knob and button is tweakable in real-time giving you the feel and sound of a true analog oldie.

The Ion has 8-voice polyphony with 3 oscillators per voice, and is 4-part multi-timbral. It offers continuously variable wave shapes (sine waves can morph into square waves), plus osc-sync and FM synthesis. 16 filter types are included, along with two LFOs, Sample & Hold, and an Arpeggiator-all of which sync to MIDI clock. A powerful and intuitive modulation matrix is built in, as well as a 40-band vocoder that does not use up any polyphony. External stereo audio can be processed through the filters, effects, or the vocoder.

Though not a true analog like the Andromeda A6, the Ion is capable of creating a wide variety of sounds from warm thick analog pads all the way to gritty monophonic leads and basses, as well as some funky and realistic sound effects. The Ion also simulates the best of the classic analogs such as Oberheims, Roland Jupiters, Arps, Moogs, etc, largely due to its great filters - there is hardly any aliasing even on the highest tones. The Ion also comes equipped with not one but two modulation wheels, both assignable to mods in the mod matrix (LFOs only assignable to mod wheel 1). The Ion has an amazing range of tonal possibilities.

Alesis Ion Image

The chic design, layout, and large backlit screen make editing on the Ion a dream! The Modulation Matrix is easy to understand and can route any modulation parameter to almost every component of the Ion!! All parameter knobs (excluding master volume & menu knob) are 360 degree pots allowing you to twist all the day long! A 160x160 graphic display provides instant visual feedback as a parameter is edited. Along with having 512 patch settings (all user-rewritable), the Ion has 64 multi-timbral setups. All parameters including arpeggiator settings are stored with each preset.

The ION keyboard contains 49 velocity-sensitive keys, 4 analog outputs and 2 stereo analog inputs (all balanced and using 24-bit conversion), 4 individual insert effects, a stereo master multi-FX processor, and an internal universal power supply. Expression and sustain pedal ports as well as headphone jacks are also there. For those who want a versatile synth and can't afford the A6, this is the synth for you - arguably one of the best 'virtual-analog' synths for awesome, analogue-like sounds.

The Ion inspired a "Mini-Me" version of itself in the Micron. It's the exact same synth as the Ion, except housed in a small 3-octave keyboard with only a few real-time controls. It has a few new features such as pattern and phrase sequencers and more filter types & effects - designed for the "on the go" musician in an overall more affordable package.

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The link above will take you to an eBay search for this synth to see active listings with more images, specs and information. If you don't find it there, try looking in our forum marketplace. Our marketplace gets thousands of visits every week so make sure to check back often if you want to buy or sell a synth.

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123 Visitor comments
March 25, 2013 @ 4:21 am
(2) the MIDI implementation is confusing to say the least (needs absurd maps for using it as master knob controller, CC is crappy and limited). I tried in every way to make something good out of it - but no, it still can't stand in a mix. It has something in EVERY patch that sounds out of place. It's about 1 year that I am trying to sell it, but I always find something broken that needs repair. It's dreaded. And when I thought that, maybe, it could be my fault as a synth programmer, there came the JX8P.
March 25, 2013 @ 4:11 am
(1) I have a bunch of things to say about this one. Owning it for 5+ years, I never NEVER got comfortable with it. Beside hardware faults (NTEs anyone?) I had to struggle with a NUMBER of annoyances: sluggy keybed, sluggy encoders that skips, unnatural envelopes (I tried every curve), menù-driven mess for half of the settings, unnecessary tedious tuning control of the oscillators, not so immediate mod matrix, poor arpeggiator, poor effects, embarassing vocoder, impredictable osc phase (ruins fm), retriggering does not start from previous ADSR state (interrupts abruptly, ruining pads),
March 23, 2013 @ 11:57 am
Dont watse you time on this buggyun finished synth, the OS freezes, its full of audible glitches and pops, Yes it sounds good and the engine is strong, the JFET's are crude and archaic and WILL fail on you, The Micron is a much better built synth with almost TRIPLE the features and no sound footprint, The andromeda also has it. The micron is by far the most bang for the buck and its flawless, if controls are your thing but a knobby controller and use w micron, save your self the resale pain, these hang out for ever for sale , the microns are gone like hotcakes, owned both, kept micron.skip it.
February 10, 2013 @ 1:26 am
This synth may have it's quirks but if you get into deep programming the Ion, you can get some great evolving drones out of it. The sheer amnt of filter types is a reason I keep it alongside my Virus, Q, Microwave XT, and a few DSI MonoEvolverKeyboards. I think the Ion gets alot of criticism because it can surely emulate the classic synths with those very filters but the Ion is not known for "it's own trademark sound", yet I may not use it all the time, but it definitely is a great piece to have in one's toolbox with it's huge modulation matrix. A keeper for many reasons, built like a tank!
February 5, 2013 @ 12:29 am
I own a number of synths, from a Moog Voyager to a DSI PEK, etc. Just recently picked up a ION. I have to say that so far I have really enjoyed its capabilities. Looking forward to spending some time juicing this machine.
VSE Rating


User Rating

Rated 3.87 (813 Votes)

  • Check Price
  • The link above will take you to an eBay search for this synth to see active listings. If you don't find it there, try looking in our forum marketplace or post a wanted classified.
  • Specifications
  • Polyphony - 8 voices (4-part multitimbral)
  • Oscillators - Alesis proprietary DSP Analog Modeling: 3 oscillators per voice (Sine, Square-Pulse, Saw-Triangle).
  • Filter - 2 multi-mode filters with 16 filter types.
  • Envelopes - 3 EGs: Pitch/Mod, Filter, and the Amp have their own ADSR envelopes.
  • LFO - 2 multi-wave LFOs and 1 S&H. Ring Modulator. FM. hard&soft OSC sync.
  • Effects - 4 Individual Mono/Stereo Insert Effects and Stereo Master Multi-FX Processor (80ms slapback delay, chorus, flanger, phaser, distortion, fuzz, compression, limiter) and built-in 40-band Vocoder.
  • Keyboard - 49 keys (velocity, release velocity sensitive).
  • Memory - 512 Patches, 64 Multi-timbral Setups.
  • Arpeg/Seq - Arpeggiator: MIDI-sync-able multiple-pattern plus *random* feature.
  • Real-Time Controllers - 30 360-degree Parameter Knobs, 2 Assignable Modulation Wheels, Assignable Pitch Wheel.
  • Control - MIDI (4-part multitimbral) IN/OUT/THRU
  • Date Produced - 2003
  • Resources & Credits
  • Images from Alesis and

    Info provided by Christian and Lars Lien.

    Reviewed December 2007.

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