I love unusual instruments, especially ones that have visual appeal when played. That's why the Alesis airSynth ($249) grabbed my attention. To play it,

I love unusual instruments, especially ones that have visual appeal when played. That's why the Alesis airSynth ($249) grabbed my attention.

To play it, you simply wave your hand over the dome. The airSynth tracks your hand position and modifies the sound (pitch, volume, filter settings, and so on) in response.

New Wave

The airSynth's dome-shaped Axyz controller houses an infrared beam and an array of sensors. The sensors pick up the reflected infrared waves as your hand passes over the dome. That gives you 3-D control over the sound: the x-axis is controlled by moving your hand left to right; the y-axis by moving front to back; and the z-axis by moving up and down. A different parameter is assigned to each axis, and the parameters vary from patch to patch (although the z-axis usually controls volume).

Because it's an infrared sensor, the airSynth is unaffected by bright lights. To test that, I pointed a desk lamp at the dome, and the airSynth worked without a hitch. However, the Axyz dome has no sensitivity knob. Consequently, some of the sounds require that you touch the dome to work their magic.

The airSynth includes a digital waveform generator and uses subtractive synthesis. It uses an Alesis effects processor to generate effects. None of the airSynth's sounds are programmable.

The instrument has only one moving part: the program knob. To select one of the 50 programs, turn the knob until the desired program number appears on the two-digit LED screen, then press the knob. The Hold feature is also controlled by the program knob: if you're playing a sound and you want to sustain it, tap the program knob. Tap the knob again to disengage Hold. That's all you need to know to play this instrument.

The airSynth has a pair of RCA inputs and outputs and is powered by a wall wart. The inputs allow you to send an audio source through the device, although none of the programs process the sound and there is no onboard control for balancing the mix of internal and external sounds. The airSynth can be attached to a mic stand and includes four rubber feet for skid-free use on a tabletop.

A 38-page manual and a printed Program chart are included. Thoughtfully, the list of the Programs, how to load them, and an explanation of Hold mode are printed on the bottom of the device.

Music from the Æther

The sounds are categorized as Tone, Percussion, SFX, High Five, or Rhythm. The Tone group offers a selection of pitched sounds, some of which are theremin-like. Generally, these have a range of an octave or two and require some practice if you want to play them melodically with precision. The Percussion and SFX categories are self-explanatory, and High Five holds five programs that could easily fit under one of the other headings.

Within the first four categories, my favorite Programs are the Phonemeanon, which offers voicelike timbres; Whispering Wind, which sounds like formant-shaped noise; and the weird distorted sounds of Sabre Tooth. A handful of the sounds are a bit corny for my taste, so I ran the airSynth through a ring modulator and tape-delay simulator to spice them up.

The Rhythm category is a collection of simple loop builders: five “sequencers” and four “auto-melody generators.” These allow you to set up a repeating percussion track, bass line, or melody line. Once you set up a loop, you can mute individual instruments by touching different parts of the dome. Although getting the exact notes you want is a bit tricky, the looping Programs are some of the finest and most satisfying features of the airSynth.

There is no MIDI or digital I/O, so you can't automatically sync the airSynth with an external device. You can set the tempo using the Global Tempo Program. The airSynth remembers this tempo until you change it or power down.


The airSynth is the epitome of a plug-and-play instrument. It's especially nice if you want an easy-to-use instrument that provides electronic color. At a recent gig, I combined it with the Alesis airFX, which proved to be a formidable combination, both sonically and visually.

If you like simple but quirky gadgets, try your hand at the airSynth. You'll be surprised at how inspiring it can be.

Overall EM Rating (1 through 5): 4
Alesis; tel. (401) 295-9000; e-mail; Web