Subwoofer, Sweep Function; Subwoofer, Driver Function; System, General Function - JBL BASS550 Service Manual

Powered Subwoofer
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 any rattles, clicks, buzzes or
any other 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 Bass550 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.
BASS550
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