Review: Applied Acoustic Systems Chromaphone 2

A great-sounding, easy-to-use physical modeling instrument
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Chromaphone represents a fairly recent entry in Applied Acoustic Systems’ (AAS) stable, having been released less than three years ago. The Version 2 update keeps with the consistent user interface design of AAS’ other virtual instruments, but the new GUI is only a small facet of the instrument’s redesign. Chromaphone 2 works as a standalone instrument on Mac and Windows computers, and supports AAX, AU, RTAS, and VST formats.

Chromaphone 2’s GUI divides into three main pages: Play, Edit, and Effects. Play features basic effects and performance parameters such as clocksync and vibrato settings, and an arpeggiator, which is new. At first glance, the arpeggiator may seem bland, until you discover that you can edit which notes play in the strip at the bottom of the page. Still, I wish note durations for the arpeggiator were more flexible rather than uniform values across the board.

Though version 1 was called a percussion synthesizer, Chromaphone 2 is labeled an “acoustic object synthesizer” with added string modeling and additive synthesis capabilities. You can mix the output of the resonators and weight the balance positively or inversely by following keyboard position. Chromaphone 2 provides basic subtractive synthesizer parameters—filters, an LFO, and an envelope generator—and these are behind many of the synth-like pads, washes, and sweeps.

With Chromaphone 2, you can run the resonators in series or parallel and integrate filtering and effects as needed. With Version 2 comes the new Drumhead resonator, and a quick trip to the kits and kit-piece banks shows its effectiveness. The kicks sound deep and authentic, or depending on other parameters, as synthetic as you please. Many of the snares have a slightly pronounced and more authentic-sounding metallic ring and acoustic snap, compared to the snares using the Membrane or Plate resonators from Chromaphone 1. A lot of great drum sounds were created by combining Drumhead with other resonators, usually Plate and Membrane or Hollow tube.

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A/B comparisons between factory presets of the two software versions revealed that Chromaphone 2 sounds brighter, with a bit more high-frequency detail overall, but I couldn’t tell precisely why. Although the instrument’s engine has not been overhauled, the effects have, and the addition of an equalizer to the instrument might have something to do with it.

The mallet sounds are very versatile, ranging from woody and warm marimbas to bright, cool-sounding vibes, and on into exotic-sounding hybrid instruments with unusual, coruscating, acoustic halos. (Think Magic Piano from the Korg M1.) Thankfully, Chromaphone 2 is backward-compatible with Chromaphone 1 patches, and I was able to quickly load my own work along with Martin Walker’s marvelous KitNetix banks. Many of Chromaphone’s percussive instruments cry out for microtonal tunings, and Version 2 adds support for Scala tunings, which loaded in without a hitch.

Chromaphone 2 is another of Applied Acoustic’s great sorties into physical modeling. The streamlined user interface invites experimentation, all while providing authentic-sounding percussion instruments. The interface illustrates how acoustic properties are generated, making it an excellent resource for teachers. I heartily suggest that you download the fully functional demo of the program at the AAS Web site.


Easy to understand interface. Drumhead resonator. Effects. Arpeggiator. Support for Scala tunings.


Nothing significant.


Among Marty Cutler’s current projects are the Fiscal-Modeling Synthesizer, the Paramedic Equalizer, the Lopez Filter, and the Orthopedic Hat.