Once you’ve connected the airFX to your system, it’s time to have some fun! The airFX contains 50 programs that you select with the program knob. The LED display will show the program number with a period at the right, indicating that the program is selected but not loaded. Pressing down on the program knob loads the program and makes the right hand period disappear. While I first found this annoying, it’s actually quite clever in that you can locate a new program while continuing to use another.

Now it’s time to wave at the Axyz controller, which sends an infrared beam out of the top of the unit. There are sensors all around the dome that see the light when it is reflected back. By moving your hand around the dome, you reflect the light to different sensors, and this changes the sound of the effect.

There are three sets of sensors in the Axyz controller. The X-axis sensor reads your hand position from left to right, the Y-axis sensor reads your hand position from front to back, and the Z-axis sensor reads how close your hand is to the sensor. Each of the programs in the airFX uses data from the sensors to vary different parameters in real time. Although not every program uses all three axes, most do and Alesis provides a handy chart that describes each program and its parameters.

Bringing your hand to within about six inches of the Axyz controller lets you hear the effect. If you’ve found a particular hand position that sounds good, you can use the Effect Hold feature to freeze the current effect. Just stop your hand when you like the effect, then press and hold the program knob. A decimal point will appear between the two digits in the display, indicating that the Hold function is set, and you can remove your hand. To release the effect and return to normal operation, you press the program knob again and the decimal point will disappear.

The Hold function can also be used as a Bypass. This will turn off the Axyz controller so that you don’t accidentally trigger an effect. Just move your hand well away from the Axyz controller and press and hold the program button. This effectively disables the airFX. Press the knob again to return to normal.


The 50 programs in the airFX cover a wide variety of effects, and range from well behaved to completely out-of-control. Some work better on music than they do on voice tracks, and I’ll limit my comments to the latter.

The first preset is called “Pitch Out” and is one of the best. It only uses the Z-axis, but bringing your hand down on the Axyz controller causes your track to gradually be pitch shifted down by up to two octaves. It sounds very much like slowing down a record (that’s vinyl, you remember that don’t you?) without changing the tempo or timing. Most effective.

“Lord of the Flies” applies a nice vocoder effect that works well with VO. Moving your hand left and right adjusts the pitch of the vocoder synth, while moving up and down alters the balance between vocoding with the synth tone and with noise. Up and down movement controls the mix between vocoded sound and dry.

“Overdrive” applies high-cut and low-cut filtering along with some particularly nasty distortion. Each of these effects is assigned to the X-, Y-, and Z-axes respectively, and turns a clean VO into some wonderfully trashy noises. The manual sums it up well, saying “Makes your CD player sound like it’s been thrown out of a moving bus.”

“Decimator” is the equivalent of downsampling digital audio to 8 bits, with provisions for controlling both the “sample rate” and the “alias filter.” It’s digital distortion at its finest. Again from the manual: “Sounds like you’re chewing on sand.” I’d have to agree.

In the filter category, there’s a nice telephone effect called (appropriately enough) “Telephone.” You get to control both the cutoff frequency and the bandwidth, and this effect responds very well to circular hand motions.

“Snake Bite” is a pretty clean high-pass filter, and works best when the resonance is high, so keeping your hand mostly toward the front of the unit and moving it from side to side works best. This sounds great on a big voice.

“Formented” applies formant filtering to your tracks, turning all the speech into vowel sounds. This filter is more effective with female VO, in my opinion, but it has a high fun factor.

Phasors and flangers are provided in bulk, and generally respond best when your hand is quite close to the Axyz controller, since the Z-axis controls the mix. In particular, “Liquid Metal” is a very lush 25-band phasor, with parameters for varying both frequency and feedback.

“Ghost Flange” is an excellent recreation of a vintage 70’s ADA flanger, complete with the deep swooshes. Your hand controls the depth, feedback amount, and delay time, so you’ll want to get aggressively physical with this effect.

“Fazed Out” provides a mix of phasing and flanging, with phase controls on the X-axis, flange controls on the Y-axis, and feedback on the Z-axis. This effect is the most pronounced of all the phasors and flangers.

“Kung-Fu Panner” lets you pan a track from left to right by just waving your hand from side to side over the Axyz controller. How cool is that? And “Stop It” does exactly what its name says; it pots a track down to near-zero with a wave of your hand.

There are three separate pitch-shifting effects in addition to “Pitch Out.” They each respond only in the X-axis, and shift pitch up to the right, and down to the left. I thought “Gender Bender” was the most interesting of these, as it shifts the pitch up or down in four discreet steps each.

Then there is a group of effects that generate their own synthesized sounds. “Skratch!” generates a record-scratching sound when you move down, while “Beatbox” gives you the sound of a cheesy kick drum on the left side of the controller, and an equally cheesy hand clap on the right side. This one is a two-handed effect for sure.

“War!” is just plain noisy and would make an interesting drop on its own, with controls for lowpass filter frequency, decay, and volume. “Haunted Landscape” gives you spooky wind effects with controls for filter frequency and resonance, while “Sci-Fi Theater” delivers a truly spooky synth tone that’s right out of a 50’s monster movie.


Of the 50 programs provided, at least half of them work well on speech. The others are also fun, but really need music or broad sound effects as source material to make them shine. All of the effects are of uniformly high quality, and in bypass mode the airFX was clean and did not color the sound.

Not only am I impressed with the quality of the effects, but with the speed with which you can work using the airFX. This is a real time device, and you can get some really nice noises out of it in very short order. The airFX is in no way programmable, which to me adds to its speed. You just pick from the varied effects provided, and get to work.

In use, I found that the most radical changes in the effects occurred when I moved my hand around the Axyz controller in a circular fashion and close up, thereby activating all three axes quickly. Each individual effect has a “sweet spot” that you’ll find quickly. Some effects respond better to bringing your hand down, while others go absolutely nuts if you wave the edge of your hand from side to side.

It didn’t take me long to figure out how to emphasize just one or two words in a VO track with a particular effect. Likewise, slow sweeping hand movements worked great on long music beds, gradually changing the color of the sound. Once you try it, you’ll find it’s all very intuitive and loads of fun, even if you do look a bit silly doing it.

The Alesis airFX retails for $249. For more information, call Alesis at 800-525-3747, or visit their website at