4
REAR PANEL DESCRIPTION
POWER Indicator
When the
POWER
switch is turned on and
the linecord is connected to an active AC power
supply, this indicator lights green to let you know
that you’re ready to rock and roll. The cool blue
LED on the front of the cabinet works in the
same way.
FULL RANGE INPUT
These are female XLR-type connectors that
accept a balanced line-level signal from a mixing
console or other signal source.
THRU (FULL RANGE OUTPUT)
These are male XLR-type connectors that pro-
duce exactly the same signal that is connected
to the
FULL RANGE INPUT
jack. Use it to daisy-
chain several SWA1501s together off the same
signal source.
HIGH PASS (MID/HIGH FREQ) OUTPUT
These are male XLR-type connectors that pro-
duce the frequencies above 120Hz. Connect these
to a pair of full-range active speakers or to an am-
plifer/passive speaker combination. The SWA1501
reproduces the frequencies below 120Hz.
SUBWOOFER LEVEL Control
This adjusts the subwoofer level. The center
detent position provides 15 dB of headroom with
a n4 dBu input signal. Use this as a
starting point for setting the balance between the
subwoofer and the main speakers.
PHASE
This switch reverses the polarity of the system.
Depending on the placement of the SWA1501
subwoofer relative to the full-range speakers, you
may get a better low-frequency response in the
room if you reverse the polarity of the subwoofer’s
signal. Experiment with this switch to determine
which position sounds best.
THRU
(FULL RANGE OUTPUT)
LIMIT
SIGNAL
THERMAL
POWER
HIGH PASS
(MID/HIGH FREQ)
OUTPUT
SUBWOOFER
CONTROL
FULL RANGE
INPUT
PARALLEL
120Hz
NORMAL
REV 180
PHASE
L
R
SUBWOOFER
LEVEL
NORMAL
IN
OUT
L
R
ON
SWA1501
ACTIVE SUBWOOFER
DESIGNED BY MACKOIDS IN WOODINVILLE, WA, USA AND MACKIE EUROPE
COPYRIGHT ©2000 • THE FOLLOWING ARE TRADEMARKS OR REGISTERED
TRADEMARKS OF LOUD TECHNOLOGIES INC.: "MACKIE", AND THE "RUNNING MAN" FIGURE • PATENT PENDING
POWER
115V-AC FUSE AC125V-T6.3A
POWER Switch
Use this switch to turn the SWA1501 on and
off. Make sure the signal source’s level control is
turned down before you turn it on.
AC Receptacle
This is where you connect the AC linecord to
provide AC power to the SWA1501’s built-in power
amplifiers. Plug the linecord into an AC socket
properly configured for your particular model.
LIMIT Indicator
The SWA1501 has a built-in limiter that pre-
vents the amplifier outputs from overdriving the
transducers. The
LIMIT
indicator lights when the
limiter is activated. It’s okay for the
LIMIT
indica-
tor to blink occasionally, but if it blinks frequently
or lights continuously, turn down the level control
until the
LIMIT
indicator only blinks occasionally.
SIGNAL Present Indicator
This LED illuminates whenever there is a
signal present at the
FULL RANGE INPUT
con-
nector on the rear panel.
THERMAL Indicator
The SWA1501 has a thermal protection circuit
that monitors the internal temperature of the
amplifiers and heatsink. If the internal tempera-
ture should exceed a safe operating level, this
indicator lights and the signal is muted to allow
the amplifier to cool. When the temperature cools
to a safe level once again, the thermal protection
circuit deactivates and normal operation contin-
ues.
Note:
Activation of the thermal protection
circuit is an indication that you should take steps
to avoid continued thermal problems. See “Ther-
mal Considerations” on page 7.
