JBL 4730A
The JBL 4730A is a professional cinema loudspeaker. It is a 3-way, 15-inch ScreenArray™ theater system that JBL positioned for smaller cinema screens where the larger 4670 series was too much box. The record on this model is mostly professional datasheet material. No production years, original pricing, or subjective listening reviews have surfaced in the available documentation.
The engineering is well documented. The 4730A pairs a 2226H 15-inch differential-drive ceramic magnet woofer with a 2118H 8-inch midrange and a 2417H 1-inch aluminum-diaphragm compression driver, crossed over at 900 Hz and 2.5 kHz. The trapezoidal cabinet is built from 25 mm MDF. The coverage pattern is rotatable (90° x +20° to - 30°) and is designed to aim the high frequencies at the listening area regardless of screen placement. Sensitivity is rated at 96 dB (1 W @ 1 m). Maximum output is rated at 121 dB continuous and 127 dB peak. The JBL Professional datasheet lists the crossover as a passive network and rates the system at 300 W continuous pink noise (IEC 268-5), 600 W program, and 1200 W peak into a nominal 8 ohms.
The secondary market has one point of contention. At least one reseller listing claims the 4730A is bi-amp only, with the woofer powered separately. The JBL Professional datasheet gives a single passive input rating for the whole system. Given the manufacturer's own documentation, the passive reading is the safer one. Still, confirm the wiring configuration with the seller before you commit an amplifier to it.
The 4730A was introduced alongside a broad group of JBL Professional models - the 4508, 4515, 4530, 4618, 4622, 4633, 4638, 4645, 4648, 4655, 4670, 4671, 4675, 4676, 4682, 4691, 4698, 4731, 4732, 4733, and 4734. The exact year of that introduction isn't pinned down in the record. It's described as derived from the 4670 series, scaled down for smaller rooms. Studio Sound (November 1991, p.20) covered the broader professional loudspeaker market of the era, but didn't specifically review the 4730A.
- Type: 3-way ScreenArray™ cinema loudspeaker
- Drivers: 2226H 15" woofer, 2118H 8" midrange, 2417H 1" compression driver
- Crossover: 900 Hz / 2.5 kHz (passive)
- Frequency response: 60 Hz – 20 kHz (±3 dB); 45 Hz – 22 kHz (–10 dB)
- Sensitivity: 96 dB (1 W @ 1 m)
- Max SPL: 121 dB continuous / 127 dB peak
- Power handling: 300 W continuous pink noise / 600 W program / 1200 W peak
- Impedance: 8 ohms nominal
- Coverage: 90° x +20° to –30° (rotatable)
- Enclosure: Trapezoidal, 25 mm MDF
- Connectors: Neutrik Speakon NL4 and barrier strip
- Dimensions: 610 x 660 x 567 mm (24.0 x 26.0 x 22.3 in)
- Weight: 32.2 kg (71 lb) net; 36.8 kg (81 lb) shipping
eBay Listings
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