Resources for the Vintage Analog Synthesizer · Over 300 pages of historical and technical information compiled, written and edited by Chris Ryan <email@example.com>  · Site hosting supported by donation (see list of contributors) · Since 1999
The Chroma has a fascinating history. The last keyboard designed by ARP, the pioneering instrument designer of the 1970s, it almost never saw production. Get the scoop here, including an exclusive interview with the product manager and one of the main hardware/software engineers from the ARP/Fender team.
Synthesizer von Gestern
Matthias Becker very kindly granted permission to post the two Chroma tracks from his CD Synthesizer von Gestern (“synthesizers of yesterday”) Volume 1. These show off the sonic capabilities of the instrument quite nicely; the CDs are still available from Matthias.
There was not a massive ad campaign for the Chroma, but the instrument was advertised regularly in 1982 and 1983, at least in Keyboard Magazine. Josef Zawinul and Herbie Hancock endorsed the instrument; and there are a few other general ads.
Service Centres that can help you repair and restore your instrument, along with articles on the Chroma dual-channel voice boards and the rare but well-integrated pressure sensor by David Clarke [21030085++] — and much more.
The ChromaTalk mailing list is a forum for owners, active since 1999 (archives are available). Discussion ranges from troubleshooting issues to Chromas for sale. In addition, we have over 600 Chromas, Expanders, and Polaris keyboards listed in the instrument registry, with owners past and present, anecdotes, music played and recorded and technical war stories. Join us!
There are a number of manuals for the Chroma, for the musician through the technician. Most are available here in PDF; the Performance Manual, Programming Manual, Service Manual, and Interface Manual in hypertext. Other docs include the Parameter Chart; Service Notes; and Field Change Notices.