JBL 300 - Manual (Page 7)

7 www.jbl.com
En
g
lis
h
OPERATING THE SUBWOOFER
TURNING THE SUBWOOFER ON AND OFF
Set the subwoofer’s Power Switch to the “On” position.
If the subwoofer’s Power-On Mode Switch is set to “Auto,” the •
subwoofer will automatically turn itself on when it receives an audio
signal, and it will go into Standby mode after it has received no
audio signal for 20 minutes. The subwoofer’s LED will glow green
when the subwoofer is on and will glow red when the subwoofer is
in Standby.
If the Power-On Mode Switch is set to “On,” the subwoofer will •
remain on at all times. The subwoofer’s LED will glow green.
If you will not be using the subwoofer for an extended period – for
instance, if you’re going on vacation – set the Power Switch to the
“Off” position.
SUBWOOFER ADJUSTMENTS: CROSSOVER CONTROL
NOTE: The Crossover Control functions only
when you are using the Line-Level In L/R
Connectors. The Line-Level In LFE Connector
bypasses the subwoofer’s built-in crossover and
the Crossover Control.
The Crossover Control adjusts the subwoofer’s
built-in crossover between 50Hz and 200Hz.
The higher you set the Crossover Control, the
higher in frequency the subwoofer will operate
and the more its bass will “overlap” that of the
satellite speakers. This adjustment helps achieve
a smooth transition of bass frequencies between the subwoofer and
the satellites for a variety of different rooms and subwoofer locations.
To set the Crossover Control, listen for the smoothness of the bass.
If the bass seems too strong at certain frequencies, try a lower
Crossover Control setting. If the bass seems too weak at certain
frequencies, try a higher Crossover Control setting.
SUBWOOFER ADJUSTMENTS: VOLUME
Use the Subwoofer Level Control to set the
subwoofer’s volume. Turn the knob clockwise
to increase the subwoofer’s volume; turn the
knob counterclockwise to decrease the volume.
Once you have balanced the subwoofer’s
volume with that of the other speakers in your
system, you shouldn’t have to change it.
Notes on Setting Subwoofer Volume:
s
setting for music is too loud for films, while
the ideal setting for films is too quiet for
music. When setting the subwoofer volume, listen to both music
and films with strong bass content and find a “middle ground”
volume level that works for both.
I f your subwoofer always seems too loud or too quiet, you may •
want to place it in a different location. Placing the subwoofer in a
corner will always tend to increase its bass output, while placing it
away from any walls or corners will always tend to lessen its bass
output.
SUBWOOFER ADJUSTMENTS: PHASE
The Phase Switch determines whether
the subwoofer driver’s piston-like
action moves in and out in phase with
the satellite speakers. If the subwoofer
were to play out of phase with the
satellite speakers, the sound waves
from the satellites could partially cancel
out the waves from the subwoofer,
reducing bass performance and sonic impact. This phenomenon
depends in part on the placement of all the speakers relative to each
other in the room.
Although in most cases you should leave the Phase Switch in the
“Normal” position, there is no absolutely correct setting for the Phase
Switch. When the subwoofer is properly in phase with the satellite
speakers, the sound will be clearer and have maximum impact, and
percussive sounds like drums, piano and plucked strings will sound
more lifelike. The best way to set the Phase Switch is to listen to
music that you know well and to set the switch in the position that
gives drums and other percussive sounds maximum impact.
CROSSOVER
50 (Hz) 200