OPERATION
Power On
Plug your subwoofer’s AC cord into a wall outlet. Do not use the outlets on the back of the receiver.
Initially set the Subwoofer-Level Control £ to the “min” position.
Turn on your sub by pressing the Power Switch § on the rear panel.
Turn on your entire audio system and start a CD or movie soundtrack at a moderate level.
Auto On/Standby
With the Power Switch § in the ON position, the Status LED on the top will remain lit in red or green to indicate the On/Standby mode of the subwoofer.
RED = STANDBY (No signal detected, Amp Off)
GREEN = ON (Signal detected, Amp On)
The subwoofer will automatically enter the Standby mode after approximately 10 minutes when no signal is detected from your system. The subwoofer will then power ON instantly when a signal is detected. During periods of normal use, the Power Switch § can be left on. You may turn off the Power Switch
§for extended periods of nonoperation, e.g., when you are away on vacation.
Adjust Gain
Turn your Subwoofer-Level Control £ up to the halfway position. If no sound emanates from the subwoofer, check the AC-line cord and input cables. Are the connectors on the cables making proper contact? Is the AC plug connected to a “live” receptacle? Has the Power Switch § been pressed to the “On” position? Once you have confirmed that the subwoofer is active, proceed by playing a CD, record or cassette. Use a selection that has ample bass information.
Set the overall volume control of the preamplifier or stereo to a comfortable level. Adjust the Subwoofer-Level Control £ until you obtain a pleasing blend of bass. Bass response should not overpower the room but rather be adjusted so there is a harmonious blend across the entire musical range. Many users have a tendency to set the subwoofer volume too loud, adhering to the belief that a subwoofer is there to produce lots of bass. This is not entirely true.
A subwoofer is there to enhance bass, extending the response of the entire system so the bass can be felt as well as heard. However, overall balance must be maintained or the music will not sound natural. An experienced listener will set the volume of the subwoofer so its impact on bass response is always there but never obtrusive.
Phase Control
The Phase Switch ¡ determines whether the subwoofer speaker’s pistonlike action moves in and out with the main speakers, 0˚, or opposite the main speakers, 180˚. Proper phase adjustment depends on several variables such as room size, subwoofer placement and listener position. Adjust the phase switch to maximize bass output at the listening position.
Crossover Adjustment
The Crossover Adjustment Control ¢ determines the highest frequency at which the subwoofer reproduces sounds. If your main speakers can comfortably reproduce some low-frequency sounds, set this control to a lower frequency setting, between 50Hz and 100Hz. This will concentrate the subwoofer’s efforts on the ultradeep bass sounds required by today’s films and music.
If you are using smaller bookshelf speakers that do not extend to the lower bass frequencies, set the Crossover Adjustment control to a higher setting, between 120Hz and 150Hz.
NOTE: This control will have no effect if the LFE/Normal Selector ™ is set to LFE. If you have a Dolby Digital or DTS processor/receiver, the Low-Pass Frequency is set by the processor/receiver. Consult your owner’s manual to learn how to view or change this setting.
MAINTENANCE AND SERVICE
The enclosure may be cleaned using a soft cloth to remove fingerprints or to wipe off dust.
The grille may be gently vacuumed. Stains may be removed with an aerosol cleaner, following its instructions. Do not use any solvents on the grille.
All wiring connections should be inspected and cleaned or remade periodically. The frequency of maintenance depends on the metals involved in the connections, atmospheric conditions and other factors, but once per year is the minimum.
If a problem occurs, make sure that all connections are properly made and clean. If a problem exists in one loudspeaker, reverse the connection wires to the left and right system. If the problem remains in the same speaker, then the fault is with the loudspeaker. If the problem appears in the opposite speaker, the cause is in another component or cable. In the event that your subwoofer ever needs service, contact your local JBL dealer, or visit www.jbl.com for
a service center near you.
