JBL 4348

Commentary

A 4-way floor-type monitor speaker system with inline layout.

In the low range, it is equipped with 1500 fe which is 38 cm cone type woofer.
Premium Pure Pulp Corn, which is naturally dried, is used for the diaphragm. Lightweight and low-loss EPDM foam rubber is used for the edge and NOMEX double damper with symmetric structure is used for the damper.
Equipped with JBL's unique bent-gap cooling mechanism that effectively releases heat from the voice coil, it realizes high linearity in response to continuous high power drive.

A 25 cm cone mid-bus unit, 2251J-1, is installed in the middle and low range.
This unit uses a fiber composite cone in pursuit of low distortion and power handling. The magnetic circuit uses a neodymium differential drive (NDD) system, and has a dual-gap, dual-voice coil structure with a large diameter neodymium ring magnet sandwiched between two pole pieces.

A horn type mid-high using 7.5 cm driver unit 435 al is mounted in the middle and high area.
Aluminum diaphragm, voice coil with lightweight aluminum ribbon wire, magnetic circuit with high-flux neodymium magnet, face plug with rapid-flare type used by JBL Professional Unit.
The horn section uses a constant coverage biradial horn manufactured by SonoGlass with 90 ° horizontal x 40 ° vertical directivity.

045 ti which is a 2.5 cm driver unit is mounted in the high range.
The diaphragm is equipped with a pure titanium diaphragm with an integrally molded edge and a lightweight aluminum ribbon voice coil wrapped around it. The magnetic circuit is also equipped with a high-flux neodymium magnet, which provides high sensitivity, high output, and high durability.
The horn is a 60 ° horizontal x 40 ° vertical constant coverage biradial horn manufactured by SonoGlass integrated with an attenuator panel.

The network section has a separate and independent structure for LF and MF to UHF.
In addition to using high-quality parts for the network elements, jBL's unique charge-coupled linear definition system is adopted, and nonlinear distortion is eliminated by applying a DC bias to the capacitor.
In addition, it is equipped with an MF/HF/UHF independent and continuously variable attenuator.

Inline layout is adopted for the unit layout, and excellent sound image localization and sound field reproduction capability are obtained by placing each unit on the vertical line at the center of the enclosure.
The enclosure uses a bass reflex system. The board is made of 25 mm thick highly rigid MDF material, and the front baffle is 44 mm thick for additional strength. In addition, the horn unit and network of Mid high and Ultra high are housed in independent sub-cavities. The upper and lower parts are divided into two separate structures. The network is established from the powerful magnetic circuit of U f, and electromagnetic interference is eliminated. The sub-cavity has a structure that has almost no effect on the total reproduction frequency characteristics even when the ring is removed.

The exterior is finished with a walnut veneer finish. In addition, the front baffle uses the traditional blue baffle on the lower side to match the separate structure enclosure, and the upper side is dark gray to harmonize with the horn color.
The grill is a separate type, and the top and bottom can be attached and removed separately.

There are two sets of speaker terminals for bi-wiring connection and active bi-amplifier drive by switching modes.

Model Rating

Method	4-Way, 4-Speaker, Bass Reflex System, Floor Type
Unit	For Low Band : 38 cm Cone Type (1500 fe) For Middle and Low Band : 25 cm Cone Type (2251J-1) For Middle and High Area : Horn Type (7.5 cm Driver 435 al) For High Range : Horn Type (2.5 cm Driver 045 ti)
Playback frequency band	33 hz to 40 khz -6dB
Impedance	6 Ω
Allowable input	400W(RMS)
Output sound pressure level	95dB/2.83V/m
Crossover frequency	300 Hz, 1 kHz, 10 kHz
External dimensions	Width 597x Height 1,080x Depth 400 mm Grill Mounted : Depth 425 mm
Weight	90.7kg