Specifics on the 15-inch woofer and high-frequency compression driver.
Allows for minor frequency response adjustments (± 10dB range).
The is a popular 15-inch, two-way active plastic loudspeaker engineered for high-performance sound reinforcement in both portable and fixed installation settings . Renowned for its versatility, the U15a combines high-output capability with rugged construction, utilizing a Class H amplifier module to drive a 15′′15 double prime low-frequency transducer and a 1.7′′1.7 double prime diaphragm compression driver.
load. It features parallel output transistors backed by heavy emitter resistors (0.22 Ωcap omega Ωcap omega , 5W) to balance current sharing. 5. Common Fault Diagnosis and Troubleshooting Probable Cause Diagnostic & Rectification Action
: Operates smoothly between 40 Hz and 18 kHz (-3dB). Maximum SPL : Achieves 120 dB peak output at 1 meter. Beta 3 U15a Service Manual
The is a 15-inch, two-way full-range active plastic loudspeaker designed for both portable and permanent sound reinforcement. While the full "service manual" containing internal board repair details is typically restricted to authorized service centers, comprehensive technical specifications and circuit schematics for its amplifier module are available for maintenance and troubleshooting. Technical Specifications & Performance
The service manual divides the internal electronics plate into three distinct modules. Identifying these sections prevents accidental damage to high-voltage components during probing. Power Supply Unit (PSU) Located at the base of the internal PCB assembly.
The Beta 3 U15a amplifier module consists of three main sub-sections: the Power Supply Unit (PSU), the Pre-Amplifier/DSP Board, and the Power Amplifier Stage. Power Supply Unit (PSU)
| Category | Specification | | :--- | :--- | | | Two-way, full-range, bi-amplified active speaker | | LF Driver | 15" high-power transducer with a 2" (50mm / 75mm) voice coil | | HF Driver | 1.7" (44mm) diaphragm compression driver | | Frequency Response | 40Hz - 18kHz (-3dB) | | Maximum SPL | 120dB (Peak) | | Dispersion (H x V) | 50°-100° x 55° (Rotatable Horn) | | Total Power (RMS) | 400W (300W LF, 100W HF) | | Amplifier Type | Class H | | Input Impedance | Balanced: 20kΩ, Unbalanced: 10kΩ | | Input Connectors | 2 x XLR (Combo, Mic/Line switchable) | | Output Connector | 1 x XLR (Thru) | | Controls | Master Volume, Bass, Treble | | Enclosure Material | Polypropylene Injection Molding | | Mounting | 8 x M8 flying points, SMART pole mount system | | Dimensions (W x D x H) | 485 x 460 x 700 mm (19.1" x 18.1" x 27.6") | | Net Weight | 30.5 kg (67.2 lbs) | | Voltage Range | AC 220V-240V~, 50/60Hz (or AC 110V-120V~, 50/60Hz) | Renowned for its versatility, the U15a combines high-output
Unlike cheaper active speakers that use integrated multi-pin ICs (like the TDA series) for both channels, the Beta 3 U15a utilizes a high-efficiency discrete layout. The Low-Frequency (LF) Class H Stage
Measure the DC resistance of the 15" woofer (typically reads around 5-6 Ωcap omega Ωcap omega nominal speaker). Inspect LF amplifier emitter resistors.
The or serial number prefix of your U15a unit.
To prevent the pump from cracking in freezing temperatures: front-of-house (FOH) systems
If you require the specific circuit diagrams, wiring loom callouts, or the exact structural parts list for your specific generation of this loudspeaker, please provide further details below. To help narrow down your request, please specify:
Before opening the cabinet, it is critical to understand the operating parameters of the Beta 3 U15a. Operating outside these specifications during testing can permanently damage the transducers or the built-in amplifier module. Active 15" 2-Way Full Range Speaker Frequency Response (-3dB): 40Hz - 18kHz Maximum SPL (1m): 120dB / 126dB (Peak)
The is a staple 15-inch two-way, full-range active plastic PA loudspeaker used globally for live sound reinforcement, front-of-house (FOH) systems, and robust stage monitoring . Manufactured by Beta Three Professional Audio (Elder Audio) based in Dongguan, China, this heavy-duty workhorse delivers a rated power output of 400W RMS via an onboard Class H bi-amplified module.