JBL 150-4H (1988)

The JBL 150-4H is a 38 cm cone woofer released in 1988. It was originally priced at ¥100,000 per unit in Japan. Documentation is thin, but what exists points to a high-output driver aimed at the upper end of JBL's component line.

What's confirmed: it's an 8 Ω unit rated at 300W continuous program power, with a sensitivity of 98dB/W/m and a frequency response of 40 Hz to 2.5 kHz. The resonant frequency (fo) is 35 Hz, and JBL recommended enclosure volumes of 85 to 225 liters. The only external dimension recorded is depth: 160 mm. The driver was described at the time as incorporating "the latest technology" into JBL's traditional woofer design — a 38 cm cone built to move serious air.

The Japanese retailer musica-co.jp listed a pair of these units, since sold out. It described them as pushing out a "powerful low-frequency feel," which fits the specs. The same listing noted the diaphragms were in "not very good" condition, so check condition carefully when hunting these down.

One Russian vintage-audio site has a single unit available "by request," with a one-month warranty and service through their radio workshop. The site says the unit was bought at auction in Japan or the USA and stored carefully since 2017. A step-down transformer is needed for Japanese or US equipment, which is standard for that region.

Beyond that, the record is quiet. No weight, no full dimensions, no crossover data, no production end year, no magnet or voice coil details.

Known specs: