Directed Audio 750d 1500d Stereo Receiver User Manual


 
12
© 2003 Directed Electronics, Inc
The Viper 750d/1500d subwoofer
amplifiers have the capability of
connecting two or more amplifiers of the
same power rating together in a
master/slave combination for increased
power with accurate level matching. They
are the Parallel Synced Gain and External
Synced Bridged combinations.
WWAARRNNIINNGG::
DO NOT attempt to combine amplifiers of different
power ratings. These amplifier combinations work
correctly only if the Master and Slave amplifiers are
identical models.
Parallel Synced Gain
In this master/slave combination the
master amplifier pre-amp controls remain
active and the slave amplifier pre-amp is
bypassed. This allows the master ampli-
fier to control gain, filter, and sub-level
on both amplifiers.
This combination allows the amplifiers to
drive their own separate subwoofer(s)
while being synced together via an in-
phase audio pre-amp signal from the
master amplifier. Wiring connections to
the amplifier subwoofer outputs in this
combination should be standard in-phase
configurations, creating a parallel
speaker connection. (Refer to
Parallel
Synced Gain
section of this guide for
amplifier and speaker connection
diagrams.)
NNOOTTEE::
One master amplifier can control up to three slave
amplifiers in this combination. Multiple identical
master/slave combinations can be added to any
given system.
External Synced Bridged
In this master/slave combination the
master amplifier pre-amp controls remain
active and the slave amplifier pre-amp is
bypassed. This allows the master amplifier
to control gain, filter, and sub-level on both
amplifiers. This combination allows the
amplifiers to drive common subwoofer
loads while being synced together via an
out-of-phase audio pre-amp signal from the
master amplifier. In this subwoofer wiring
configuration the master amplifier sends the
positive signal to the subwoofer while the
slave amplifier sends the negative signal,
making an externally bridged speaker
connection. (Refer to
External Synced
Bridged
section of this guide for amplifier
and speaker connection diagrams.)
NNOOTTEE::
Amplifiers in this combination can only be connected
in matched pairs. Multiple matched pairs may be
added to drive separate subwoofer loads in a given
system.
Combined Amplifiers Gain
and Filter Settings
Set the Subsonic, EQ, and other filter
settings on the master amplifier to the
positions that achieve the best sound
quality. Adjustment guidelines are
discussed in the
Crossover and Gain
Adjustment
section of this guide.
COMBINING AMPLIFIERS