JBL Concert Series Loudspeaker Systems

4922 System

Features: Optimum matching of amplifier power and signal processing, electronic equipment mounted and wired, standardized interconnect cables, certified hanging hardware, stereo capability.

Description: Complete system ready to operate with addition of source and mixing equipment. Includes loudspeakers, power amplifiers, electronic crossover, signal processing equipment, racks, and cables. Pre-wired and tested.

Components:

• [2] 4870 Loudspeaker Systems
• [2] 50 foot EP-8 Loudspeaker Cables
• [1] 9922 Equipment Rack containing:
  • [1] 6260 Amplifier (HF)
  • [1] 6290 Amplifier (LF)
  • [1] 5234A Dual-Channel Electronic Crossover with high-pass filtering and 800Hz crossover cards.

4923 System

Components:

• [2] 4870 Loudspeaker Systems
• [2] 4845 Loudspeaker Systems
• [2] 50 foot EP-8 Loudspeaker Cables
• [2] 5 foot EP-8 Loudspeaker Cables
• [1] 9923 Equipment Rack containing:
  • [1] 6260 Amplifier (HF)
  • [2] 6290 Amplifiers (LF, YLF)
  • [2] 5234A Dual-Channel Electronic Crossovers with high-pass filtering and 80Hz/800Hz crossover cards.

4943 System

Components:

• [4] 4870 Loudspeaker Systems
• [4] 4845 Loudspeaker Systems
• [4] 50 foot EP-8 Loudspeaker Cables
• [4] 5 foot EP-8 Loudspeaker Cables
• [1] 9943 Equipment Rack containing:
  • [1] 6260 Amplifier (HF)
  • [3] 6290 Amplifiers (2-LF, 1-YLF)
  • [2] 5234A Dual-Channel Electronic Crossovers with high-pass filtering and 80Hz/800Hz crossover cards.

Typical System Characteristics

[1] SPL at 1 meter, continuous program. [2] Total power available into nominal system load impedances.

JBL Concert Series 4870 Loudspeaker System

A modular, high-power, two-way, biamplified loudspeaker system designed for concert reinforcement. Features concert-proven componentry, 35 Hz to 20 kHz usable frequency range, and rugged construction for touring.

Features: Concert-proven componentry, 35 Hz to 20 kHz usable frequency range, ruggedized construction, 30-degree wedge frustum shape for coherent coverage, fiberglass-reinforced finish, 14 aircraft-type hanging points.

Description: Biamplified system with dual 15-inch direct radiator loudspeakers and a 2-inch throat compression driver on a Bi-Radial™ horn. Vented enclosure made from void-free birch plywood, coated with fiberglass reinforced plastic. Tapered cabinet for tight cluster grouping.

Low Frequencies: Ported enclosure tuned to 40 Hz, using two JBL 2225H loudspeakers. Large ducts ensure freedom from vent compression.

High Frequencies: Frequencies above 800 Hz reproduced by JBL 2445J compression driver on a JBL 2380 Bi-Radial™ horn. Titanium diaphragm for robust power handling.

Physical: Cabinet tapers 15 degrees front-to-back, forming a 30-degree wedge frustum. Includes mounting provisions for optional JBL 2404 ultra-high frequency transducers. Energized via one EP-8 input connector. Optional 4870DL dolly available.

Specifications:

• System Type: Modular, direct radiating LF, two-way, externally biamplified concert reinforcement loudspeaker system
• Frequency Range (-10dB): 35 Hz to 20kHz
• Frequency Response (±3dB): 45 Hz to 16kHz
• Axial Pressure Sensitivity: LF: 100 dB/1w/1m, HF: 112 dB/1w/1m
• Power Capacity [1]: LF: 800 watts continuous program, HF: 150 watts continuous program
• Recommended Crossover: 800 Hz, 12 dB per octave minimum
• Coverage Angles: 90 degrees Horizontal, 40 degrees Vertical
• Nominal Efficiency: LF: 7.0%, HF: 30%
• Maximum SPL: 132 dB [1m, continuous program]
• Nominal Impedance: LF: 4 ohms, HF: 16 ohms
• Connectors: ITT Cannon EP-8 type
• Dimensions: 49-1/2" H x 29-1/2" W x 19-3/4" D
• Weight: 214 lbs (97 kg.)
• Finish: Dark gray fiberglass-reinforced plastic, black nylon grill

Architect's and Engineer's Specifications: Two-way system with two 15-inch LF drivers and a compression driver on a 90x40 degree horn. Frequency range 35 Hz-20kHz. Sensitivity 100 dB (LF), 112 dB (HF). Power capacity 400W (LF), 75W (HF). Horizontal coverage 90 degrees, vertical 40 degrees. Cabinet construction: void-free birch plywood with fiberglass reinforcement, 14 aircraft-type hanging points (2000 lbs rating each).

JBL Concert Series 4845 Loudspeaker System

A vented direct radiator very low frequency (VLF) loudspeaker system for sound reinforcement and playback. Provides uniform power response to 30 Hz. Cabinets are identical in size and shape to the 4870 for stacking.

Features: Concert-proven componentry, 20 Hz to 800 Hz usable frequency range, ruggedized construction, 30-degree wedge frustum shape for mutual coupling, fiberglass-reinforced finish.

Description: Vented enclosure, tapered front-to-back for tight cluster grouping. Made from void-free birch plywood with fiberglass reinforcement, handles, and aircraft-style pan fitting hardware.

Performance: Ported enclosure tuned to 27 Hz, using a JBL 2245H loudspeaker. Delivers full rated acoustic power output and maximum SPL to 30 Hz. Features large linear displacement, high power handling, and Symmetrical Field Geometry (SFG) magnetic structure for low distortion.

Physical: Cabinet tapers 15 degrees front-to-back. Fourteen system hanging points. Energized via one EP-8 input connector. Optional 4870DL dolly fits.

Specifications:

• System Type: Modular direct radiating low frequency loudspeaker system
• Frequency Range (-10dB): 20Hz to 800Hz
• Frequency Response (±3dB): 25 Hz to 250 Hz
• Nominal Impedance: 8 ohms
• Connectors: ITT Cannon EP-8 type
• Dimensions: 49-1/2" H x 29-1/2" W x 19-3/4" D
• Weight: 176 lbs. (80 kg.)
• Finish: Dark gray fiberglass-reinforced plastic, black nylon grill
• Quantity of Units:
• One: Pressure Sensitivity 95dB, Nominal Efficiency 2.1%, Power Capacity 600W, Acoustic Power Output 6 watts, Power Response 30Hz-250Hz, Max SPL 120 dB
• Two: Pressure Sensitivity 98dB, Nominal Efficiency 4.2%, Power Capacity 1200W, Acoustic Power Output 25 watts, Power Response 28Hz-125Hz, Max SPL 126 dB
• Four: Pressure Sensitivity 101dB, Nominal Efficiency 8.4%, Power Capacity 2400W, Acoustic Power Output 101 watts, Power Response 25Hz-80Hz, Max SPL 132 dB

Architect's and Engineer's Specifications: Vented direct radiator low frequency system. Acoustic power output 6.3 watts above 30 Hz. Power response +/- 3 dB, 30 Hz to 250 Hz. Power Capacity 300 watts sine wave above 30 Hz. Driver with 9.5mm peak linear displacement. Cabinet tuning frequency 27 Hz. Construction similar to 4870.

JBL Concert Series 4830 Loudspeaker System

An all-horn loudspeaker system of high performance and compact proportions, designed for external triamplification. Delivers constant directivity and uniform power response for high-level sound reinforcement.

Features: Fully horn-loaded for maximum efficiency, concert-proven componentry, constant coverage and uniform power response, 40 Hz to 20 kHz usable frequency range, ruggedized construction, equipped with castors and hanging hardware.

Description: All-horn system for external triamplification. Proven components for constant directivity and uniform power response. Crafted from void-free hardwood plywood with castors. Six hanging fittings provided.

Low Frequencies: Folded front-loading horn driven by JBL 2240, extending output to 40 Hz.

Mid Frequencies: Mid-frequency throat provides loading and constant directivity. Uses JBL's Symmetrical Field Geometry (SFG) design for uniform power response and reduced distortion.

High Frequencies: Transition at 1200 Hz. Uses JBL 2445 compression driver and 2385 Bi-Radial™ horn. Diaphragm of pure-grade titanium.

Specifications:

• System Type: Fully horn loaded three-way externally triamplified modular concert reinforcement loudspeaker system
• Frequency Range (-10 dB): 40 Hz to 20kHz
• Frequency Response (±3dB): 60 Hz to 16kHz
• Axial Pressure Sensitivity: LF: 103 dB SPL/1w/1m, MF: 106 dB SPL/1w/1m, HF: 114 dB SPL/1w/1m
• Power Capacity [1]: LF: 600 watts continuous program, MF: 300 watts continuous program above 250 Hz, HF: 150 watts continuous program above 1200 Hz
• Recommended Crossovers: 250 Hz LF-MF (12 dB/octave minimum), 1200 Hz MF-HF (12 dB/octave minimum)
• Coverage Angles: 60 degrees Horizontal, 40 degrees Vertical
• Nominal Efficiency: LF: 15%, MF: 20%, HF: 30%
• Maximum SPL: 138 dB SPL [1m, continuous program]
• Nominal Impedance: LF: 4 ohms, MF: 8 ohms, HF: 16 ohms
• Connectors: ITT Cannon EP-8 type
• Dimensions: 58" H x 22-1/2" W x 30-3/4" D
• Weight: 290 lbs. (132 kg.)
• Finish: Dark gray fiberglass-reinforced plastic, black nylon grill

Architect's and Engineer's Specifications: Three-way system, all drivers horn loaded. 60x40 degree coverage. Frequency range 40 Hz-20kHz. Sensitivity: LF 103 dB, MF 106 dB, HF 114 dB. Power capacity: LF 300W, MF 150W, HF 75W. Construction: void-free hardwood plywood, rounded corners, six aircraft-type hanging points (2500 lbs rating each).

Electronics

Input Connections: Balanced XLR receptacles with polarity reversal and ground lift switches. Parallel loop-through connector for system expansion.

Balanced Source Connections: Recommended for professional mixers. Caution regarding ground loops and RFI. Shields should be connected at one end only.

Unbalanced Source Connections: Discouraged for long runs. If used, treat as pseudo-balanced. Connect shield at load end only.

Output Connections: Wired to 8-pin Cannon EP-8 receptacles. Systems provide multiple outputs depending on model (e.g., 9922/9923 have two, 9942/9943 have four). Connections to 4845s use loop-through connectors on 4870s.

Diagrams:

• Figure 2: Input Wiring (typical) shows XLR input with ground lift and polarity reverse switches.
• Figure 3: Output Connector Wiring illustrates the 8-pin Cannon EP-8 wiring for HF, LF, and VLF connections.

Loudspeakers

General: Familiarize with performance specifications of Models 4845 and 4870 for optimal deployment. Consider physical placement to minimize interference.

Group Loudspeakers Together: Place systems close together for coherent coverage, especially at low frequencies. At higher frequencies, close placement helps reduce interference.

Use Fewer Loudspeakers: Avoid using more systems than necessary, as it can reduce intelligibility and increase interference.

Take Advantage of Cabinet Shape: The 30-degree wedge frustum shape allows moderate horizontal splay angles for tighter cluster grouping and reduced interference.

Split Clusters: If using split clusters, maintain minimal distance between them to manage interference and maintain sound quality.

Group VLF Systems: Group VLF systems (4923, 4943) into a single array for increased VLF output.

Hanging Systems

Concert Series systems use aircraft-style pan fittings for rigging. Load rating is 2000-5000 lbs per fitting. Consult a licensed structural engineer and professional riggers for system design and installation. Always use premium-grade hardware and maintain liability insurance.

Typical System Configurations:

• Figure 4: Two Loudspeaker Wide-Coverage: Shows two 4870 systems splayed at 90 degrees for wide coverage.
• Figure 5: Two Loudspeaker Medium Coverage: Shows two 4870 systems placed side-by-side with a 30-degree angle for 120-degree horizontal coverage.
• Figure 6: Four Loudspeaker Wide-Coverage With VLF: Illustrates a configuration using all 4943 components in a single array.
• Figure 7: Two Loudspeaker Wide Vertical Coverage Array: Demonstrates varying vertical angles between cabinets (20-40 degrees) for desired vertical coverage.

AC Power Connections

Systems operate on 120V AC mains (North America) with three-conductor cords. Ensure proper grounding for safety and mechanical integrity. Check local regulations for circuit and conductor current limitations.

AC Connections for Portable Applications: Use an electrician's circuit tester to verify voltage and wiring of AC receptacles.

Figure 9: North American AC Receptacle Wiring: Illustrates standard duplex receptacle wiring (neutral, hot, ground).

Powering the System Up:

1. Verify all source equipment is powered up.
2. Rotate all power amplifier level controls fully closed.
3. Switch AC power on, preferably one amplifier at a time for large systems.
4. Slowly raise amplifier level controls to pre-set positions.

Powering Down: Switch power amplifiers off first.

Level Setting Procedure: Use a spectrum analyzer and measuring microphone. Adjust levels with power amplifier controls fully open. Bypass house and program equalizers during level setting.

Rack Systems and Component Assignments

Figure 10: 9922 Equipment Rack: Shows 9922 rack with 6260 (HF) and 6290 (LF) amplifiers and 5234A crossover. Output assignments detailed.

Figure 11: 9942 Equipment Rack: Shows 9942 rack with 6260 (HF) and two 6290 (LF/VLF) amplifiers and 5234A crossovers. Output assignments detailed.

Figure 12: 9923 Equipment Rack: Shows 9923 rack with 6260 (HF), two 6290 (LF/VLF) amplifiers and two 5234A crossovers for triamplification. Output assignments detailed.

Figure 13: 9943 Equipment Rack: Shows 9943 rack with 6260 (HF), three 6290 (LF/VLF) amplifiers and two 5234A crossovers for triamplification. Output assignments detailed.

Function-Block Diagrams:

• Figure 14: Block Diagram for 9923/9943 Rack Systems with VHF Loudspeakers.
• Figure 15: Block Diagram for 9922/9942 Rack Systems with VHF Loudspeakers.
• Figure 16-19: Function-Block Diagrams for various system configurations (9922, 9923, 9942, 9943). These diagrams illustrate signal flow through amplifiers and crossovers.

VHF Transducers

Optional JBL Model 2404H VHF loudspeakers can be added to the 4870 for increased output above 10 kHz. Requires addition of a 5234A with 7 kHz crossover cards and a 6215 amplifier. Signal flow diagrams illustrate hook-up.

Loudspeaker Dolly

Optional Model 4870DL dolly available for 4870 and 4845 systems, facilitating handling and stacking.

Loudspeaker Cable Assemblies

Available assemblies include Model 9805 (5 ft) and Model 9850 (50 ft). Cables are 8-conductor, 12.5 AWG wire with 8-pin Cannon EP-8 connectors.

Electronics Cases

Accessory cases (9916RC, 9920RC) protect electronic racks in portable service. Constructed of fiberglass reinforced plywood with casters.