JBL 4642A-GS
The JBL Model 4642A is a high quality subwoofer system, featuring an advanced technology 460 mm (18 in), 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.
Transducer:
The 2241H transducer utilizes the patented Vented Gap Cooling (VGC) process*, which pumps air through the magnetic gap and directly over and around the voice coil, providing immediate heat transfer and a reduction in operating temperature. This increases power handling while reducing power compression.
Through the use of computer-aided magnet optimization and analysis techniques, JBL engineers were able to optimize magnet weight, flux density and field saturation, resulting in a 2.6 kg (6.5 lb) reduction in overall driver weight and a significant reduction in harmonic distortion. This magnet structure offers much of the weight advantage of rare earth magnet structures without the prohibitive cost, enabling the system to carry a 1200 watt continuous AES pink noise power rating.
Features:
- 1200 Watts Continuous Pink Noise, 2400 Watts Continuous Program Power Handling
- Usable response to 22 Hz (-10 dB, no EQ), flat to 22 Hz (-3 dB) with External EQ
- 2241H VGCTM Vented Gap Cooled Drivers- High Sensitivity- Low Power Compression- High Maximum-SPL Capability- Low 2nd and 3rd Harmonic- Distortion- Symmetrical Field Geometry SFGTM- Magnet Structure- Long Excursion Capability
- Approved by Lucasfilm, Ltd. for THX installations
Specifications:
TRANSDUCERS: Two JBL Model 2241H 460 mm (18 in) Low Frequency Transducers
SYSTEM:
- Rated Impedance: 4 ohms
- Minimum Impedance: 3.2 ohms
POWER HANDLING CAPABILITY:
- Continuous Pink Noise: 1200 Watts
- Continuous Program: 2400 Watts
- Peak Power: 4800 Watts
OUTPUT CAPABILITY:
Axial Sensitivity:50 Hz to 500 Hz; 101 dB, 1W @ 1m40 Hz to 100 Hz; 100 dB, 1W @ 1m
Power Compression:
At -10 dB power (120 W): 0.8 dB
At -3 dB power (600 W): 2.6 dB
At rated power (1200 W): 4.3 dB
FREQUENCY RESPONSE:
Lower Frequency Limits (no EQ):-10 dB: 22 Hz-3 dB: 35 Hz
Lower Frequency Limits (with EQ):-10 dB: 20 Hz-3 dB: 22 Hz
Recommended Crossover Frequencies:
High-pass: 20 Hz, 12 dB/octave or greater
Low-pass: 80 Hz to 150 Hz, 12 dB/octave or greater
Distortion:
2nd harmonic: <2%
3rd harmonic: <2%
System Polarity: EIA Standard. Positive voltage to RED terminal produces forward cone motion.
Input Connectors: Color-coded push terminals
Net Weight: 98 kg (216 lbs.)
Shipping Weight: 109 kg (240 lbs.)
ENCLOSURE:
- Materials and Finish: 19 mm (3/4 in) particle board with 25 mm (1 in) baffle and back panel. Extensive bracing on all panels
- Enclosure Tuning Frequency: 25 Hz
- Net Internal Volume: 506 liters (18 cu. ft)
- Dimensions: 762 mm x 1219 mm x 610 mm, H x W x D 30 in x 48 in x 24 in