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
Look for the . Pin 8 (VCC) should read 12V-14V. If pin 8 is oscillating, the startup resistor R3 (220kΩ) has drifted high. Beta 3 U15a Service Manual