Vintage JBL 4311b // Speakers / Aural Custom Restoration

The classic. The JBL 4311B is one of the most sought-after models from JBL, and this pair has been recapped, reclothed, and reimagined.

* Stands sold separately

RESTORATIONS

• Full 30-point service check
• Repainted faces
• Installed new binding posts
• Recapped crossovers
• Complete frequency sweep
• Detailed

SPECS

Type   3-Way, 3-Speaker, Bass reflex standmount loudspeaker

Sensitivity   91dB

Frequency Response   45 Hz to 15 kHz ±3 dB

Impedance   8Ω

Dispersion   90°

Output sound pressure level   91dB/W/m

Power Handling   40W(RMS) / 75W(Peak)

Enclosure volume   40L

Woofer   300mm long throw cone (2213H)

Midrange   130mm cone (LE5-10)

Tweeter   36mm direct radiator (LE25-2)

Crossover frequency   1.5 kHz, 6 kHz

Dimensions   14.25"W x 23.5"H x 11.75"D

Weight   44 lbs.

LINER NOTES

The history of some of the world's most famous and valued JBL loudspeakers traces back to the 1960s, commencing with the 4320 model. This model was a staple in many sound studios, laying the foundation for JBL's legacy. Nevertheless, professionals in the industry were seeking a monitor that was both professional-grade and compact enough to be mobile. As a response to this demand, the 4310 model was born, a product of collaboration with renowned recording studios, and it quickly gained widespread popularity.

 

However, just as the 4310 was gaining momentum, JBL underwent a change in ownership when the Jervis Corporation, under the control of Sidney Harman, took over. Among the initial personnel changes was the appointment of Irving Stern as the head of marketing. Recognizing the success of the 4310 monitors, Stern saw an excellent opportunity to tap into the consumer market. He understood that adapting these monitors for home use would necessitate enclosure modifications.

 

Despite some opposition within JBL, with concerns that making the 4310 available to consumers might reduce its appeal to professionals, a decision was reached after extensive deliberation. The configuration of the 4310 was altered while preserving the core design principles, resulting in the creation of the JBL L100 speakers designed for home use. This decision proved to be a resounding success, as the model went on to become the best-selling speaker in the company's history.

 

Meanwhile, ongoing testing of the 4310 model revealed that the uninterrupted treatment of flat deflectors did not provide the anticipated acoustic advantages. Consequently, this feature was removed from the design. To enhance the dispersion of high frequencies, a smaller-diameter tweeter replaced the original one. Additionally, adjustments were made to the crossover frequencies to achieve a smoother response. This updated version was designated as the 4311 and featured a conventional recessed baffle, along with an H.F. radiator raised to the acoustic plane of the woofer and the front edge of the enclosure. JBL recommended it as "a compact package delivering smooth, powerful, and broadband response."