JBL 4375

The JBL 4375 is a professional studio reference monitor from JBL's Pro series, designed for film and video post-production rooms where a smaller footprint was needed. The official JBL Pro product page lists it as a two-way system with a 12-inch low-frequency driver and a 1-inch compression driver on a bi-radial horn, housed in a bass-reflex (ported) enclosure. The manufacturer's specs show a frequency response of 40Hz–20kHz (–6dB), sensitivity of 92 dB SPL / 1W @ 1m, 8-ohm impedance, and 200W continuous power handling. It measures 24" × 18" × 12" and weighs 45 lbs, with 5-way binding posts for connection.

Past the manufacturer's page, the record gets thinner and a bit contradictory. An Audio Heritage forum post describes the 4375 as a three-way system with a 12-inch woofer, 5-inch midrange, and 1-inch tweeter. It also claims third-order (18dB/octave) crossover slopes, which would make it a different animal than the two-way spec sheet. The same forum source places the 4375 below the flagship 4350 and above the 4400-series entry monitors in JBL's Pro lineup, and claims it shares its driver platform with the 4425 and 4408. One user review published on the JBL Pro page (2005) called it honest in the midrange with decent low-end for a 12-inch woofer. A 2019 forum post called it "surprisingly accurate" but also said the crossover sounds "a bit thin in the upper mids" compared to the 4425.

No production years, original price, or period reviews have surfaced. Audio (August 1979, p.104) ran classified ads in the same era, but nothing reviewing this model. Collectors note these don't come up for sale often. They have been seen at roughly $1,200-$1,800 per pair on eBay and Reverb. The foam surrounds on the 12-inch woofers are prone to rot, so budget for refoaming ($80-$120 per driver) if you find a pair.

Frequency response: 40Hz–20kHz (–6dB)
Sensitivity: 92 dB SPL / 1W @ 1m
Impedance: 8 ohms
Power handling: 200W continuous
Drivers per JBL Pro: 12" LF + 1" compression driver on bi-radial horn
Crossover: 900Hz (per JBL Pro)
Dimensions: 24" × 18" × 12" · Weight: 45 lbs