The first 10 Fairchild 660 were built by Narma himself. Sherman Fairchild, who was friends with Les Paul, learned of the compressor and licensed Narma's compressor design, hiring Narma to be chief engineer at Fairchild Recording Equipment Corporation. Les Paul asked Narma if he would build a compressor/limiter.
The 660 was designed by Rein Narma, who had worked with Les Paul to build a recording mixer to use with Les Paul's Ampex 8-track. They are commonly referred to as the 'holy grail' of outboard gear. The rarity of Fairchild compressors has made them highly desirable and very valuable, with a used 660 now selling for $20,000 or more and a 670 selling for $30-$40,000 or more. The Fairchild 670, introduced shortly after the 660, is a dual-channel version.
The 660 was the first intelligent automatic volume control limiter. The Fairchild 660 is a tube-based single-channel audio compressor invented by Rein Narma and manufactured by the Fairchild Recording Equipment Corporation beginning in 1959. Fairchild Recording Equipment Corporation
