Ampex AX-300 (1971–1972)

The Ampex AX-300 was an automatic-reverse open-reel stereo tape deck for the serious home recordist. It ran at three speeds (7½, 3¾, and 1⅞ ips) and had recording and playback preamps built into the deck, so it needed no outboard electronics. High Fidelity (March 1972, p.39) reported the price at less than $650 with the wood case. It also noted an optional RC-204 remote-control unit for $39.95 that connected via a ten-foot cable. The deck measured 16¾ by 15 by 8½ inches.

Several features show up in the period advertising campaign that ran across both High Fidelity and HiFI/Stereo through 1971 and early 1972. A built-in stereo echo effect let the user add controlled feedback in both channels without external patch cords. A controlled-bandwidth circuit was included as well. The same campaign used the tagline "Verry Heavy" to describe the satisfaction of a recording session that captured every sound exactly. It claimed extremely clean recordings across the audio spectrum, a very high signal-to-noise ratio and virtually eliminated intermodulation distortion. HiFI/Stereo (September 1971, p.40) published a measured record-playback response curve. It noted a 4-dB rise at 50 Hz on the quarter-track test tape at 7½ ips, and a full-track tape measurement at 3¾ ips.

No service manual, schematic, or detailed specification sheet has surfaced in the available record. The exact production run years are not firmly documented beyond the 1971-1972 advertising window. The model appears to have been in circulation for roughly that span.

Type: Automatic-reverse open-reel stereo tape deck with built-in recording and playback preamps
Speeds: 7½, 3¾, 1⅞ ips
Track format: Quarter-track stereo (heads compatible with full-track test tapes)
Dimensions: 16¾ × 15 × 8½ inches
Price: Less than $650 with wood case (1972); optional RC-204 remote $39.95
Features: Stereo echo effect, controlled bandwidth, automatic reverse