Tuesday 18 June 2019

JBL BASS 550 powered sub woofer test procedure


Equipment needed: The “Source” AM/FM turner/CD player with remote control, Function/signal generator/sweep generator.  
Multimeter.
Cable - Phono plugs (RCA) and speaker cables. 
RCA Y-cable
Subwoofer, General Function
1) Connect both right and left phono jack (RCA) inputs to signal generator and the “Source” Tape/Aux. input jacks. Use Y-cable if necessary from mono source.
2) Connect Bass550 subwoofer to the “Source” with 13 pin Din cable.
3) Plug in subwoofer, turn power switch on; red LED should light.
4) Turn on generator, adjust to 100 mV, 50 Hz.
5) Push “power” button on the “Source”, (display should now be active); press “Tape/Aux” button, adjust volume (on Source) so display reads “VOLUME 30”.
6) Turn up level control on subwoofer full clockwise.
7) LED on subwoofer should cycle to green; bass response should be heard and felt from port tube opening.
Subwoofer, Sweep Function
1) Follow steps 1-7 above, using a sweep generator as a signal source.
2) Sweep generator from 20Hz to 300Hz. Listen to the cabinet and drivers for anyrattles, clicks, buzzes or anyother noises. If any unusual noises are heard, remove driver and test.
Subwoofer, Driver Function
1) Remove one or both drivers from cabinet; remove + and - wire clips.
2) Check DC resistance of driver; it should be approximately 5.8 ohms.
3) Connect a pair of speaker cables to driver terminals.
Cables should be connected to an integrated amplifier fed by a signal generator. Turn on generator and adjust so that speaker level output is 4.0V.
4) Sweep generator from 20Hz to 1kHz. Listen to driver for any rubbing, buzzing, or other unusual noises.
System, General Function
1) Connect Bass 550 subwoofer to the “Source” with supplied 13 pin Din cable.
2) Attach all five satellite speakers to the supplied speaker cables, terminating in a molex connector plugged into the subwoofer.
3) Plug in Bass550 subwoofer, turn power switch on; red LED should light.
4) Push “power” button on the “Source”; (display should now be active).
5) Toggle “surround mode” button on front panel or with remote control until “NORMAL” appears.
6) Toggle “rear speaker” button on front panel until “REAR SPEAKERS” is displayed in upper left corner.
7) Adjust volume (on Source) so display reads “VOLUME 30”.
8) Using remote control, press “TONE” button.
9) White noise should be heard, cycling from Left, Center, Right and Rear speakers in succession.
10)Press “TONE” button again to halt test.

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