JBL J820M
Documentation on the JBL J820M is thin. The model shows up in the period press - HiFI-Stereo (September 1995, p.44) ran a test report that included real-room frequency response measurements of a pair of speakers - but the surviving record doesn't confirm even basic details like production years, original price, or driver configuration. The archive has only a few fragments, all from that same September 1995 issue.
The test data is partial. A measurement cited in HiFI-Stereo (September 1995, p.46) showed maximum output at 135 Hz, falling by 6 dB at 80 Hz, with port radiation dominating below about 90 Hz. That suggests a ported (bass reflex) enclosure. The same report noted output dropped off fairly steeply below that region, though distortion stayed under 10 percent down to 20 Hz. The J820M appears to have had modest low-frequency extension, with the port doing the heavy lifting in the upper bass.
Beyond those measurements, the record is empty. No confirmed specifications, dimensions, or historical context have surfaced in the materials available to the Archive. If you own a pair or have original literature, the J820M is a candidate for a proper entry.
eBay Listings
As an eBay Partner, we earn from qualifying purchases. This helps support our independent vintage technology research.
Related Models
- JBL 075
- JBL 077
- JBL 120Ti
- JBL 124A
- JBL 124H
- Braun AUDIO-1 (1965)
- Braun AUDIO-250 (1965)
- Magnavox Component Systems (1972)
- Acoustic Research AR (1967-1976)
- Acoustic Research 11