The C20 was a highly flexible preamplifier which was self-powered and could be used with any stereo power amplifier or pair of mono power amplifiers. Its modern and attractive appearance was designed by George H, Kress & Associates, industrial designers.

The front panel was made of glass with a gold anodized aluminum trim. Earlier versions had plastic panel with brass trim. Controls included mode selector (Reverse, stereo, L, R, Mono left, Mono right); balance; phase (0 or 180); HF cutoff filter (flat, 9kc or 5kc); loudness ( flat to max); volume with power switch; input selector ( aux, tape, tuner 1, tuner 2, phono 1 (stereo or mono), phono 2 (stereo or mono), tape head 1 tape head 2); record compensator (bass switch, 0, 300, 400, RIAA, LP, tape, treble switch: tape, -5, -10, -12, RIAA, LP) bass and treble controls; rumble filter; tape compare switch; tape jacks and switch and headphone socket.

The back panel contained all of the inputs and outputs. Outputs included L+R, main (2 pair), tape. Inputs included High level inputs: tape compare, aux, tape, tuner 1, tuner 2. Low level inputs: phono1 : crystal ceramic, magnetic 2-10mV and 10-70mV, phono 2: crystal ceramic, magnetic 2-10mV and 10-70mV, tape head 1: 2-10mV and 10-70mV, tape head 2: 2-10mV and 10-70mV.

Other back panel features included low frequency trim controls, ground binding post and 5 AC outlets (4 switched, 1 unswitched).

Priced at $269 when new (1962 Allied Radio Catalog), today's value is around $1500.00 for an attractive working example. Prices for mint originals would be higher.

The C-20 was replaced by the C-22 in 1963, which had similar specifications to its predecessor. Production of the C-22 ceased in 1968 but a commemorative edition was re-issued by McIntosh in 1995, priced at around $2,500.00.

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Photographs courtesy of Barry Nachman