Fairchild Model 663 Compact Compressor
No larger than a slide-type attenuator, and the little box that gave every microphone channel its own compressor.
Overview
The pitch in Fairchild's own advertising was that you could finally afford a compressor on every mike channel — a claim built entirely on the Model 663's size, which the company described as no larger than a slide-type attenuator, actually 1½ inches narrow. That footprint is the whole story here. Compressors of the period were rack-width boxes, and Fairchild's argument was that the 663 could be integrated directly into a console instead of patched around one. Audio (March 1967, p.16) ran the Compact Compressor in its advertising pages with the tagline about creating "up tight levels" that contribute to presence and loudness — marketing copy, to be clear, not a measured verdict.
What the 663 actually does is straightforward on paper: up to 20 dB of compression, with no increase in distortion according to the manufacturer's literature. The attack time is fixed at 40 milliseconds, while the threshold and release are both variable and brought out to the front panel — release adjustable from .3 to 7 seconds. That release range is the flexible part, and it's what separates the 663 from a set-and-forget limiter.
Fairchild's manual language is emphatic about the absence of artifacts — no distortion despite the amount of compression used, no thumps, no noise. Whether or not every unit lived up to that in practice, the design intent is clear: this is a broadcast- and recording-oriented compressor meant to sit quietly in a signal chain, not a character piece.
There is a variant worth knowing about. The Model 663 NL came with unity gain plus additional gain if needed, with +18 dBm output — so if the plain 663's gain structure doesn't suit a particular console, the NL version covers it. Collectors should check which one they're looking at before assuming gain behavior.
The price in period advertising was $158.00 for the Model 663, which puts it in context against the rest of Fairchild's line: this was the affordable, per-channel member of a family that otherwise included the rack-mounted 658A and the compact 658B Reverbertron reverb systems and the 664NL Program Equalizer. Fairchild sold the 663 as the piece you bought in quantity, and its size and price were the reasons why.
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