'link': Beta 3 U15a Service Manual

: Features a 15" high-power low-frequency (LF) transducer with a 50mm voice coil and a 1.7" diaphragm compression driver for high frequencies (HF).

: If the unit fails to power on, check the 14A protection fuse . Always replace it with a fuse of the exact same amp rating as specified in the U15a User Manual . Beta 3 U15a Service Manual

: Frequency response ranges from 40Hz to 18kHz (-3dB) with a maximum peak SPL of 120dB at 1 meter. : Features a 15" high-power low-frequency (LF) transducer