JBL L400

Name: JBL L400
Brand: JBL

Documentation on the JBL L400 is thin. The record shows a 3-way bookshelf loudspeaker in JBL's L-Series, built around a 10" woofer, a 5" midrange, and a 1" soft dome tweeter. Period studio listings from Mix Magazine (January 1986, p.144) show JBL monitors in professional recording environments. The spec sheet that circulates across a handful of databases agrees on the essentials - 8-ohm nominal impedance, 87 dB sensitivity, a frequency response of 47 Hz to 40 kHz, and a recommended amplifier range of 10 to 150 watts, with crossover points at 1.1 kHz and 5 kHz.

Beyond that, the record gets murky. No production years, original retail price, or launch context survive in any source we've found. Cabinet construction, port type, and crossover component details are undocumented. Even the physical specs disagree. One database lists the L400 at 31 kg, another at 23 kg, and the two sets of dimensions floating around don't reconcile either. The conflicting figures are left out rather than guessed at.

What exists is anecdotal. A single eBay listing from 2024 offered a pair at $850, with the seller reporting they sounded great and were especially smooth in the highs for jazz. The same listing noted one dead tweeter and minor cosmetic cabinet scratches. A trade-in dealer listed the L400 at $480.