JBL 4311/4311WX (1973–)
The JBL 4311 arrived in 1973 as the successor to the well-regarded 4310. It turned up in small studios, control rooms, and adjustment rooms. It was a 3-way, 3-speaker bass-reflex bookshelf monitor, built for near-field use where space was tight but accuracy still counted. The woofer was a 30 cm cone unit (the 2212), paired with a 13 cm cone midrange (LE5-2) and a 3.6 cm cone tweeter (LE25). The midrange driver sat in its own back cavity. That was deliberate: it isolated the midrange from the woofer's rear radiation and kept it clean.
The crossover points were set at 1.5 kHz and 6 kHz. JBL included continuously variable controls for the middle and high ranges, so engineers could tailor the response to the room. Frequency response was rated at 45 Hz to 15 kHz ±3 dB, with a new JIS sensitivity of 91 dB and 8-ohm impedance. JBL rated allowable input at 40W continuous program, though other sources list power handling at 75W. The enclosure held 42.5 liters internal volume, measured 360 x 600 x 300 mm and weighed 19 kg.
Two finishes were offered: the standard gray and the walnut-veneered 4311WX. The WX carried a slightly higher price in Japan (¥205,200 vs. ¥193,800 for the standard version around 1975). The front baffle placed the woofer at the top, and the speakers could be suspended if needed. A period JBL "Pro-Note" from July 1973 indicated the 4311 was due for production that August, with the 4310 continuing alongside it until at least November of that year.
Collectors should watch for a few common issues. The 2212 woofer uses a fixed edge, so edge rot isn't a concern. Many surviving units do have dented center caps on the woofer, the LE5-2 squawker, or the LE25 tweeter. Capacitor drift in the network can cause tonal imbalance, and the level controls are prone to scratchy noise. Working pairs with original grilles, badges, and packaging command a premium. Single units and parts/repair pairs are common on the used market. A German forum user recalled running the 4311 with tube amplifiers when it was current and remembered the combination fondly, though another commenter suggested an amplifier with sufficient damping factor for best control.
The 4311WX-B variant has been listed as a "professional-grade" system for commercial applications, and the 4311B appears in listings as a "3-Way Control Monitor." The archival record is thin on these variants. The A/B revision differences (possibly Alnico vs. ferrite magnets) are discussed but not definitively documented, and no technical specs for the 4311A or 4311WXA have surfaced.
Similar items on eBay
No exact JBL 4311/4311WX listings are live right now — these searches show current JBL and similar vintage audio gear on eBay:
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