JBL LSR305, Owner'S Manual

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LSR310S Subwoofer - The subwoofer weighs 19 kg (42 lbs.) Unpacking the subwoofer does not require you lift the
subwoofer. However, you will need to rotate the subwoofer in the carton. If you are unable to perform the following
steps without assistance, please request help from another person.
• Remove the outer shipping carton, if one exists.
• Place the carton on the floor with the bottom facing upward.
• Open the bottom flaps of the carton and remove any protective packing materials from the bottom of the
subwoofer. Open the bag that protects subwoofer, exposing the subwoofer’s four feet.
• Gently rotate the carton so the bottom of the carton is facing the floor and the four feet of the subwoofer are
in contact with the floor.
• Gently lift the carton allowing the subwoofer and protective packing materials to slide out of the carton and
remain on the floor.
• Remove the protective packing materials and documentation from the top of the subwoofer. Save the
cartons and use the above procedure in reverse when you want to repack the units for shipment.
PLACEMENT
3 Series speakers are designed to deliver exceptional imaging in any room. To get the most out of your speakers,
follow these recommendations:
• Locate the four self-adhesive rubber pads supplied with LSR305 and LSR308 speakers. Position and attach
these to the bottom surface of the speaker close to each corner.
• Position each LSR305 and LSR308 speaker in a vertical orientation with the tweeter on the top.
Vertical orientation eliminates phase shift and cancellation of frequency response that occurs when the
distance of the woofer to the ear is different from the distance of the tweeter to the ear.
• Angle the speakers so the high-frequency transducer in each speaker is aimed directly towards the ear
of the listener.
• Ideally, LSR305 and LSR308 Series speakers should be placed on suitable speaker stands, rather than on
the work surface. This will reduce resonance and deterioration of low frequency performance that occurs
through the speaker’s mechanical coupling with the work surface.
• For optimum imaging, the left speaker and the right speaker should be placed symmetrically in the room,
so each speaker is the same distance from adjacent walls and reflective surfaces.
• The speakers should be placed so the position of the listener and the two speakers form an equilateral
triangle. Adjusting the distance between the speakers will affect the quality of bass heard at the listening
position. You can experiment with speaker placement to find the placement that produces the preferred
bass response, imaging and when listening to stereo material, produces a strong “phantom” center in
which vocals and some instruments seem to originate from a point between speakers.
• The listening distance can be determined according to your preference, the acoustics of your room and the
maximum SPL (Sound Pressure Level) you want to hear at the listening position. You can find the speaker’s
maximum SPL at 1 Meter in the Specifications Section at the end of this manual. Each doubling of listening
distance will reduce the SPL at the listening position by 6 dB in an acoustically absorptive room, but only 3
or 4 dB in an acoustically reflective room.
LSR310S Subwoofer placement: The low frequency driver of the 310S is mounted on the bottom panel of the
subwoofer. Before placing the subwoofer, make sure the position on the floor is free of any large objects that can
interfere with or damage the woofer. In a stereo system, The LSR310S Subwoofer should be placed directly on the
floor, located between the Left and Right Speakers. In a surround sound system, the subwoofer can be located
between the Left and Center or between the Right and Center channel Speakers. The distance of the subwoofer
from the listening position can be adjusted to produce the optimum balance of bass in the system. Placing the
subwoofer close to a wall or in a corner generally will increase the amount of bass heard in the room. Experiment to
determine the Subwoofer placement that produces the best balance and quality of bass in the system.