JBL 4638 Dual 15″ 800 Watt Low Frequency Loudspeaker System

The JBL 4638 low Frequency system is designed for cinema use and general reinforcement where smooth power response and accurate reproduction are essential.

The 4638 employs the latest in JBL low Frequency Transducer technology, offering exceptional performance benefits. The JBL 2035H 380 mm (15 in) Transducer employs a coppersleeved magnetic pole piece which reduces internal flux modulation and provides a more stable magnetic field. This substantially lowers both second and third order harmonic distortion.

The copper-sleeved pole piece design of the 2035H also creates a flatter Impedance curve, resulting in a nearly perfect resistive load throughout the operating range of the Transducer, and producing a more constant power response characteristic below 1 kHz. This helps maintain a smoother and more natural sounding power response transition between the low and high Frequency devices in the Crossover region, resulting in, among other benefits, more accurate reproduction of dialog throughout the listening area.

The 2035ʼs Voice Coil operates in a large Symmetrical Field Geometry (SFG™) magnet structure to further reduce harmonic distortion to inconsequential levels. With a Sine Wave input of 100 Watts, third harmonic distortion is no greater than 1.0% and second harmonic distortion is no greater than 0.8% at any Frequency between 100 Hz and 500 Hz.

The enclosure is constructed of dense stock and is extensively braced on all panels. Net internal Volume is 225 liters (8 cu ft) and the enclosure is tuned to 40 Hz. Port area is large, ensuring minimum turbulence at full input at low frequencies.

Features:

• Usable Response to 30 Hz
• 100 dB Sensitivity, lW, 1 m
• 800 Watts Power Capacity1600 Watts Continuous Program
• Two 380 mm (15 in) Low Frequency Transducers with Exceptional Performance
• Direct Radiator Ported Enclosure

• COMPONENTS:1-JBL 4508A low Frequency enclosure2-JBL 2035 380 mm (15 in) low Frequency Transducers(Note: Components may be ordered separately for field assembly)
• SYSTEM:
• Rated Impedance: 4 Ohms
• Minimum Impedance: 3.5 Ohms
• POWER HANDLING CAPACITY:
• AES: 800 Watts
• Long Term Average per EIA RS-426A²: 1000 Watts
• Continuous Program³: 1600 Watts
• OUTPUT CAPABILITY:
• Axial Sensitivity: 100 dB @ lW, 1 m
• Half-space reference efficiency: 8%
• Maximum acoustical power output5: 64 Watts
• Power compression:at -10 dB power (80 W): 0.6 dBat -3 dB power (400 W): 1.9 dBat rated power (800 W): 3.2 dB
• Frequency Response:
• Lower Frequency limits (No external EQ):-3 dB: 45 Hz-10 dB: 30 Hz
• Recommended Crossover frequencies:High-Pass: 40 Hz, 12 dB/Octave min.Low-pass: 500 or 800 Hz, 12 to 24 dB/Octave
• Distortion:2nd Harmonic (typical):

Subwoofer 2x18 2241H, 1200W AES, 4Ω, 100dBSPL/1W/1M, 22Hz-3dB με EQ και γρίλλια. Εγκεκριμένο από την lucasfilm LTD., για THX. (762H x 1219W x 610D mm). 98kg.

Single 460 mm (18 in) High Power Subwoofer.
Approved by Lucasfilm, Ltd. for THX® system installations.

The 4642A is a high quality subwoofer system, featuring an advanced technology 460 mm (18“), low frequency transducers mounted in a direct radiator, bass-reflex enclosure for smooth response to the lowest audible frequencies. The 4642A is ideal for low-frequency augmentation of either analog or digital soundtracks in motion picture theaters and for general sound reinforcement applications.

NOTE: Consult the product page for more information on the 4642A's 2241H transducer.

Key Features:

• 1200 Watts Continuous Pink Noise, 2400 WattsContinuous Program Power Handling
• Usable response to 22 Hz (-10 dB,no EQ), flat to22 Hz (-3 dB) with External EQ
• 2241H VGC (Vented Gap Cooled) Drivers
  – High Sensitivity
  –  Low Power Compression
  –  High Maximum-SPLCapability
  –  Low 2nd and 3rd Harmonic Distortion
  – Symmetrical Field Geometry (SFG) Magnet Structure
  –  Long ExcursionCapability
• Approved by Lucasfilm, Ltd. for THX®installations

Specifications:

• Low Frequency Drivers: (2) 2241H
• Frequency Range: 22 Hz - 500 Hz (-10dB)
• Power Capacity (Continuous Pink Noise): 1200Watts
• Power Capacity (Continuous Program): 2400Watts
• Sensitivity: 101 dB SPL (1W, 1m,3.3ft.)
• Crossover Frequency: 80-150 Hzrecommended
• Nominal Impedance: 4 Ohms
• Dimensions (HxWxD): 30" x 48" x 24" (762 x 1219 x610 mm)
• Net Weight: 98 kg (216 lb)

The JBL 4645C is a single 460 mm (18 in) high power subwoofer. It is approved by Lucasfilm Ltd. for THX� system installations.