L-Acoustics X8, Руководство пользователя

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Maintenance
X8 user manual (EN) version 2.0 30
Acoustical check
It is necessary to do an acoustical check to verify the correct installation of the diaphragm.
Procedure
1. Load a FLAT preset on an LA4X / LA8 amplified controller.
2.
Connect a low frequency generator to the active input of the amplified controller.
3. Connect a voltmeter to the output of the amplified controller and check the output voltage.
Risk of damaging the HF driver
The output voltage must not exceed 1 Vrms.
4.
Connect the HF driver to the output of the amplified controller.
Use ear protection to set the sound level before testing.
5. Send a test signal of 1.5 kHz at 1 Vrms for 5 seconds.
The sound should remain pure and free of unwanted noise.
Troubleshooting
The sound resulting from the test is not pure and high-frequency harmonic distortions or strange vibrations are audible.
Possible causes
— There are foreign particles on the air gap.
— The number of shims is wrong.
— The screws used for reassembly are too loose.
Procedure
1. Repeat the disassembly procedure.
2.
Clean the air gap thoroughly.
3. Repeat the reassembly procedure.
Pay close attention to the number of shims and the position of the diaphragm.
Apply the recommended torque.
4.
Repeat the acoustical check.
If a buzzing sound is still audible, it might be necessary to add an extra shim on the air gap.