Aphex ESP-7000 (1987)
Documentation on the Aphex ESP-7000 is thin. Almost everything known comes from a single period lab report. Len Feldman tested the unit for db Magazine (July/August 1987, p.50), and that write-up is still the clearest picture of what the processor was and how it performed.
The ESP-7000 was Aphex Systems' entry in the late-1980s surround boom. It was an "Enhanced Separation Processor" aimed at multi-channel home systems, and it drew on Aphex's studio pedigree. Feldman described three operating modes: Music and Cinema processing modes, plus a Stereo Bypass that took the unit out of the circuit entirely. That was useful for A/B comparison and level setting (db Magazine, July/August 1987, p.50). He noted that without enhancement, adjacent-channel separation (center vs. front, center vs. right) is only 3 dB (db Magazine, July/August 1987, p.51). That is exactly the problem the processor was designed to address. The ESP-7000 did not carry the Dolby "Double-D" license mark, but it proved compatible with Dolby-encoded material as well as ordinary stereo programming.
Feldman's measurements:
- Main outputs (Music mode): 20 Hz–20 kHz, −2 dB (manufacturer claimed 12 Hz–50 kHz, −1 dB)
- Subwoofer output: 20 Hz–150 Hz, −5 dB (manufacturer claimed 12 Hz–150 Hz, −3 dB)
- Dynamic range: measured 99 dB vs. 96 dB claimed
- Max output / input level: 4.2 Vrms (+12.5 dBV), confirmed
The supplied remote was a fourteen-button membrane unit. It covered power, separation enhancement amount, decoding mode, front/rear and left/right balance, and master volume (db Magazine, July/August 1987, p.51). Beyond Feldman's review, little else seems to be recorded - no prices, no production run details, no successor.
Similar items on eBay
No exact Aphex ESP-7000 listings are live right now — these searches show current Aphex and similar vintage audio gear on eBay:
As an eBay Partner, we earn from qualifying purchases. This helps support our independent vintage technology research.