JBL 136H (c. 1981)

Name: JBL 136H
Brand: JBL

The JBL 136H is a 38 cm (15-inch) cone woofer, sold as a raw driver and not as part of a complete speaker system. The record on it is thin. No production years are documented, and the only firm date reference is an original price of ¥57,000 (one unit) from around 1981. What is known comes largely from a Japanese audio database entry and a handful of parts suppliers.

The 136H was designed with the same characteristics and sound quality as a JBL studio monitor woofer. It has a 10.2 cm voice coil wound with copper wire and a magnetic flux density of 12,000 gauss. It also has a unique mass control ring, which JBL said extended the playback band into the ultra-low frequency range while improving low-distortion characteristics. The surround is foam, and foam surrounds eventually deteriorate. Re-foam kits are readily available from at least two European parts suppliers.

Known specifications are as follows:

Type: 38 cm cone woofer unit
Allowable input (continuous program): 200W
Impedance: 8 Ω
Sound pressure level: 93 dB/W/m (audio-database.com) / 94 dB/W/m (ldsound.info)
Frequency characteristic: 25 Hz to 2 kHz
fo: 16 Hz
Voice coil diameter: 10.2 cm
Magnetic flux density: 12,000 gauss
Enclosure internal volume: 85–170 liters
Depth: 143 mm
Weight (packed): 11.7 kg

No documented information says which JBL speaker systems used the 136H, though an eBay listing pairs it with the L300 in its title. No reviews, owner opinions, or market pricing data have surfaced. One forum post asks about re-edging a pair of 136H woofers with new foam surrounds, which fits the foam-edge design and the availability of repair kits. An instruction manual exists and is available as a free PDF download, but its contents are not documented here.