Koss 1020 (circa 1978–1979)
Surviving information on the Koss 1020 is thin. The record shows that Koss appears to have offered a loudspeaker model under the name CM 1020. The few period references are all advertisements, not reviews, so independent performance data is essentially absent.
The advertising campaign ran in several audio publications between 1978 and 1979. It was built around what Koss called the “Koss Theory of loudspeaker design.” The company claimed a computer-assisted approach to three-bandpass speaker engineering, with the CM 1020 as the result. Specific claims included a 3 dB gain in electrical efficiency, a -3 dB point of 31 Hz in the low band, and a crossover region from 300 Hz to 3.5 kHz handled by a “performance synthesized” design. High Fidelity (March 1978, p.48) carried the ad, as did HiFI-Stereo (May 1978, p.129) and Hi-Fi-Stereo-Buyers (March 1979, p.7).
It is not clear whether the model number “1020” is shorthand for the CM 1020 or a separate product altogether. The advertisements consistently use the “CM 1020” designation. No service manuals, measured specifications, production totals, or original pricing have surfaced. The 1020 does not appear in any of the other Koss pages on this archive (ESP-950, ESP9, HP/6, K/135, K-6), and no crossover with those headphone-focused models is evident.
If you have a pair of CM 1020s, a brochure, or any documentation, the Archive would welcome the contribution.
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