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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Are you looking to buy or sell a Alesis Ion? Post an ad in Gear For Sale or a request in Gear Wanted. For spare parts and repair services check out Gear Services & Other Goods. Our forums also has a Buyer’s Guide section where you can ask for advice on buying synthesizers.

123 Visitor comments
September 23, 2013 @ 6:58 pm
I have one and am very satisfied with it. If you pick one up, make sure the OS is updated...or else it can be prone to crashing, etc. Since updating, i've had no problems with it whatsoever. Granted effects are not the most robust, but there is A TON there for the offering. I've heard a few people pan it for sounding thin, but i've never had that issue with my sounds- especially with drive/compression effects. make no mistake, this is a very respectable little synth if you know how to get the most out of it.
August 22, 2013 @ 7:00 pm
Anyone who has ever owned any decent analog synthesizers will immediately realize how thin this synth is, its cool to play and has a fair amount of features but its thin, quality could be better and while ive never experienced anything too major , i have come across some bugs in the earlier os but os 3 seems to have addressed this, Unless you get a great deal theres better synths out there to spend your money on.
August 13, 2013 @ 11:15 am
Drawing on my own experience I have to disagree with cali78,I have played my Ion side by side with a friends Micron and there was no difference audible in so far as artifacting, noise etc

granted this is my experience,and as they saying goes YMMV. yes the Micron is a superb machine and its nice to have the extra added features,but I will never sell my Ion as i love the ability to edit live on the fly without the need for a computer monitor and/or an external controller. at 46 I have owned and played my share of analogs,digital and va's,and the Ion and Micron are among my very favorite.
August 6, 2013 @ 4:26 pm
@Cali78 now if we could just add in all the extra sequencing, phrase recording and separate drum synthesizer or add all the knobs to the micron?
EASY! the Micron responds almost perfectly to CC and NRPN "Non-Registered Parameter Number"... so all you have to do is build yourself a control surface that spits ot the MIDI CC and NRPN data to control the main board of the Micron.
Take a look at: the midibox hardware platform at: and build yourself an ION using a Micron main board for the synth engine. You could actually do a better interface than the ION has that way.
August 1, 2013 @ 10:52 am
The MFETS and JFETS have actually been upgraded on the micron, as an owner of both boards the micron is much clearer and lacks the audible tone, artifacting? that the ion has. Even with the updated filters i still find myself running the Ion thru the microns filters much cleaner, quieter, now if we could just add in all the extra sequencing, phrase recording and separate drum synthesizer or add all the knobs to the micron? its almost like they put the wrong engines into the wrong bodies with these synths? Ion makes a wonderful micron controller! I guess let the reviews speak for this board.
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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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