The Chroma has a
velocity-sensitive keyboard consisting of 64 weighted, levered wooden keys with optional
polyphonic pressure-sensitivity. Few units included the original factory pressure sensor. The Chroma's sixteen synthesizer channels consist of one voltage-controlled oscillator (VCO), waveshaper,
filter, and amplifier under software control via multiplexed analog voltage control channels, grouped into eight A/B pairs. Although the oscillators, filters and amplifiers themselves are voltage controlled, the overall control of the synthesizer channels is entirely in software. The embedded computer generates thirty-two
ADSR envelopes (two per channel, one with delay) and sixteen
LFO sweep signals in software. Signals from the controls are encoded digitally, processed by the computer, and sent to the synthesizer channels on the voice cards.
Sound programs can use one channel per voice to produce sixteen-voice
polyphony. Channels can be paired together for thicker, 8-voice sounds. The Chroma uses an electronically reconfigurable system that allows its VCOs,
VCFs and VCAs to be virtually patched in various configurations. Patch data and program parameters are stored digitally and can be saved or loaded from cassette. Each
sound program uses one of fifteen internal configurations linking the oscillators, filters, and amplifiers in different ways to create varied timbres, including series or parallel filter routing, oscillator sync, filter FM, and ring modulation. ==Hardware==