Beta Three (Beta 3) U15a is a 15-inch two-way full-range active loudspeaker manufactured by Elder Audio
The serves as the definitive engineering and repair guide for maintaining, troubleshooting, and restoring the Beta Three U15a Active Loudspeaker . This 400W two-way full-range speaker utilizes a Class H bi-amplified design to drive a high-power 15-inch low-frequency woofer and a 1.7-inch high-frequency compression driver. Audio technicians, live sound engineers, and electronic repair professionals rely on the service manual and its accompanying Elder Audio PM300 Amplifier Circuit Schematics to manage component-level diagnostic workflows and safety procedures.
15" Two-way full-range active speaker with built-in bi-amp module.
If the speaker shows no signs of life (no power LED, no sound), the problem is likely in the power supply section. Beta 3 U15a Service Manual
Here is a consolidated look at the U15a’s specifications compiled from the official manufacturer datasheets and other resources:
) on the rear panel, along with a switchable Mic/Line input.
Reading Open (OL): Burned out voice coil. Transducer replacement required. Beta Three (Beta 3) U15a is a 15-inch
: Hardwires the power transformer to handle alternate AC input lines (110V–120V or 220V–240V). Schematic Diagnostics & Main PCB Troubleshooting
The is a professional 15-inch two-way full-range active speaker designed for high-output performance in both portable and permanent installations. It features a built-in bi-amp power amplifier module delivering 400W RMS (300W LF + 100W HF) to a 15-inch high-power transducer and a 1.7-inch diaphragm compression driver. Key Technical Features
I can provide the targeted component values or wiring schematics you need. Share public link 15" Two-way full-range active speaker with built-in bi-amp
: Unplug the power cord entirely before removing the rear amplifier assembly.
: Operates smoothly between 40 Hz and 18 kHz (-3dB). Maximum SPL : Achieves 120 dB peak output at 1 meter.
For a full copy of the official repair documentation, it is recommended to contact support directly or a certified repair center, as servicing active electronics requires specialized knowledge.
Passive aluminum heatsink (Optional forced air depending on regional revisions) 2. Safety Precautions and Tools Required Safety Warnings
The "story" behind the centers on a workhorse of the professional audio world: a rugged, 15-inch active speaker known for its versatility in both touring and permanent installations. This manual is the essential guide for technicians maintaining a high-performance system designed for "Houses of Worship," nightclubs, and outdoor venues. The Legend of the U15a