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
December 5, 2009 @ 10:14 pm
The Left and Right channel output muting FETs (Field Effect Transistors) turn on for a second when the unit is turned on to momentarily mute the audio output. Unfortunately after all that spohisticated design that went into producing the synthesizer they chose a cheap generic FET that fails by shorting with any kind of static electricity applied to the audio output connectors (like if you ever see a spark jump when you touch or plug something in to a metal connector). The FETs are labelled J111 and you can replace them with NTE468 FETs or equivalent, which will be much more robust. I have replaced them - not too hard a fix if you are a repair tech like myself. If you are a musician but don't like getting into the circuitry, get friendly with someone who likes working on electronics stuff (offer him / her some of your old/broken stuff, backstage passes to your after concert parties, etc... ).
December 2, 2009 @ 11:29 am
i bought one for power electronics sounds. for its price tag it does a great job. making beefy patches is a breeze. i find diving into menus crap, but it really outdoes any other digital synth ive played on. the graphics are handy, giving you an idea of what's going on in its virtual world. the mod matrix works a bit like modular synth, but this is frustrating because it's not as hands-on as a real modular, but it's many knobs truly make up for this. the drive function on the ion is essential. a little 'tube overdrive' goes a long way. i've had my ion for some time now, and i haven't even gotten close to exploring all of it's potentials. many recommend it for beginners. the graphics will help a newbie understand how synthesis works though.
November 16, 2009 @ 5:24 pm
Probably one of the best sounding keyboards ever manufactured. I prefer this board over all others for synth leads, pads, arps, et al. It is just amazing. All that said, mine suffered from a bad main volume pot. I had little to no sound in the left main out (main and headphone) + a buzzing noise. All told it has cost me about $150 to fix. I think I'm going to sell it because it's expensive to own. I will opt for its little brother with the same sound engine. Alesis should be sued for the piss poor build quality of this otherwise phenomenal synth.
November 9, 2009 @ 2:01 am
Hey Freddy, the keys ARE full size (in fact same size as in all my other synths, Prophet08, Prophet 5, Moog Voyager, Korg Mono/Poly, etc...)

Second, your Ion suffers from the self-edit syndrome because of bad pots. That's why you have to send it back so they can replace them with new ones.

Just so you know.I've had mine for 2 years now, and only one of the pots is starting to be flacky now (the tempo adjust), but not to the point of self editing though...
October 19, 2009 @ 7:10 am
Good: Diverse routings. 3 oscillators. Some VA filters sound very convincing. Sometimes this synth sounds kind of bright for my liking though, but some of the emulations are spot on.

Bad: The keys are not full-sized. We get effects, but no reverb, the effect you'd probably want the most. So, I have to lug an outboard 'verb to gigs.

Ugly: The display is flat to the front panel. Put it on the top tier for live gigs and you'll be standing tippy toed to read the screen.

Potentials: I have a weird bug where screen suddenly looks like I've adjusted the ADSR but I have not. I wrote to ask where to get fixed locally: nope. They insisted I send it to a particular location on the E. coast. (not even someone to fix it in Chicago or LA - What?) 2nd and 3rd emails never returned. Lousy support!

Buy again? Probably. It's a useful synth in studio and for gigging analog-like sounds without lugging along vintage gear.
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Rated 3.86 (808 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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