JBL PS1400 Preliminary Service Manual - Subwoofer Controls Ps1400
4
Subwoofer Controls PS1400
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¡ On/Auto Switch – When
left in the “Auto” position, the
PS1400 subwoofer will
automatically turn on or go into
standby mode, depending on
whether it detects an audio
signal. When no signal is being
sent, the PS1400 will remain in
standby mode. When it senses
an audio signal, it will
automatically turn itself on and
begin playing. If the PS1400
does not sense a signal for
about twenty minutes, it will
switch itself into standby
mode. When this switch is
left in the “On” position, the
PS1400 will remain on, whether
or not program material is
playing.
™
™ LF Crossover Switch – This
switch is used to engage the
PS1400’s internal crossover
when it is stacked with the
PT800 tower module, and when
no external crossover is being
used. In the “Normal” position,
the internal crossover is
engaged, and provides an
electronic 130Hz crossover for
the subwoofer which precisely
matches the passive 130Hz
crossover point of the output
terminal to the PT800. The
crossover is precision-
designed to create a smooth,
integrated floorstanding
speaker system when the
PS1400 and PT800 are stacked.
In the “Separated” position,
the PS1400 provides an
electronic 300Hz rolloff for the
subwoofer, which should be
augmented by the low-pass
crossover in the external
audio/video receiver or
processor. In this mode, the
PT800, whether or not it is
stacked with the PS1400,
should be given only a high-
passed amplifier signal. That
signal should be crossed over
at 80Hz.
£
£ LF Level Control – This
control allows you to adjust the
level of the subwoofer within a
range of +/– 5dB. Start with the
control positioned at 0dB,
which is flat (neutral bass
level). If bass response is
unsatisfactory, due to either
your room acoustics or as a
matter of taste, experiment
with this control until the
desired bass level is achieved.
This control only affects all
information being received by
the speaker-level input.
¢
¢ Polarity (Phase) Switch –
Use the “Normal” position
whenever the PS1400 and PT800
are stacked and the internal
crossover is used. It should
also be used when an external
crossover is used and all
amplifier channels are in phase.
The “Reverse” position may be
used when the PS1400 and
PT800 are separated, and due
to wave cancellation, bass
response is improved in this
position. “Reverse” may also
be selected when different
amplifiers are used that
have different polarity
configurations.
PERFORMANCE
SERIES
CAUTION
RISK OF ELECTRIC SHOCK
DO NOT OPEN
“WARNING: TO REDUCE THE RISK OF FIRE OR ELECTRIC SHOCK,
DO NOT EXPOSE THIS APPLIANCE TO RAIN OR MOISTURE.”
“AVERTISSEMENT: POUR PRÉVENIR LES RISQUES D’INCENDIE OU
DE CHOC ELECTRIQUE, EVITER D’EXPOSER CET APPAREIL A LA
PLUIE OU A L’HUMIDITE.”
MANUAL
AUTO
ON/OFF
SEPARATED
NORMAL
-2 0
-5 5
LF CROSSOVER
REVERSE
NORMAL
MIN MAX
– +
POLARITY
ON
OFF
POWER
LFE LEVEL
SYSTEM INPUT
LFE /SUBWOOFER
INPUT
LF LEVEL
®
NRTL/C
CSA 22-2
UL 1492
PN 336609-001
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™
£
¢
∞
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dB