Synthesizer design and manufacturing company founded by Alan R. Pearlman, and the second largest such company after Moog Music for most of the 1970s. Originally founded under the name "Tonus" in 1968, the company was renamed using founder Pearlman's initials when it released its first product, the lavish and expensive 2500 modular system, in 1970. Despite the 2500's high cost, it soon became popular with university music departments. ARP's next product, the semi-modular 2600, provided many of the functions of a modular in a smaller pre-configured case; it established ARP among first-rank synth and keyboard players of the decade.
Subsequent products included the Odyssey, a performance synthesizer similar in concept and features to the Minimoog and the Omni string synthesizer, the company's best-selling product. However, management problems, including a conflict in direction between Pearlman and company president David Friend, resulted in excessive spending and miniscule profits. In 1977, over Pearlman's objections, Friend launched a project to develop the Avatar guitar synthesizer. The Avatar consumed most of ARP's research and development money, was late to market, and didn't work very well when it was finally introduced. The resulting cash-flow problems constrained the company's ability to develop further products, and without any new products, sales declined and the company was finally forced into bankruptcy in 1981.
The company's last development effort was the Chroma, its first practical effort to develop a polyphonic synth with patch memory. ARP ran out of money a few months short of the Chroma being ready for market. Chief engineer Philip Dodds rescued the project by reaching an agreement with CBS to sell the Chroma design and prototypes to them, and then re-launch the project under CBS's ownership. The Chroma eventually went into production under the Rhodes brand name, which CBS owned at the time.
Today, ARP synths, like vintage Moogs, are highly sought after on the collectors' market.