11
LD-1A with MSL-4 and 650-P
A typical MSL-4:650-P ratio is 2:1 but separate Sub and Mid-
Hi level controls on the LD-1A allow the ratio to vary while
maintaining control of the spectral balance of the system. The
Lo Cut filter for CH1 Mid-Hi should be
in
to correct the LF
rise between the MSL-4 and 650-P.
MSL-4
650-P
CH 1 Sub
CH1
Input
CH 1 Mid-Hi
LD-1A
Line Driver
Set the MSL-4 and 650-P to the same polarity.
LD-1A with Flown PSW-2 and MSL-4;
650-P on the Floor
Including subwoofers in a flown cluster provides a smooth
frequency image because the low and mid-hi frequencies are
produced from loudspeakers located close together. The identical
dimensions of the PSW-2 and MSL-4 allow them to be easily
flown together.
The CH 1 Mid-Hi output drives the MSL-4 with the Lo Cut
filter
in
. The CH 1 Sub and DS-2 outputs drive the 650-Ps and
PSW-2s with the DS-2 & Sub Crossover switch
out
, which
sends a full-range signal with independent level control to
each loudspeaker.
650-P
subwoofer
on the floor
MSL-4 and
PSW-2
flown in
same cluster
CH 1 Mid-Hi
CH 1 Input
CH 1 DS-2
CH 1 Sub
LD-1A
Line Driver
Set the MSL-4 and PSW-2 to the same polarity. The polarity for
the 650-P depends on the height and distance of the measure-
ment position from the flown and subwoofer systems.
LD-1A with Flown MSL-4, DS-2P/DS-4P, and CQ;
650-P on the Floor
This example shows the LD-1A integrating a complete system
of self-powered loudspeakers for a large venue. Although the
diagram shows half of the system with channels 1, 3, and 5,
channels 2, 4, and 6 can be used with identical connections for
the other half. The MSL-4, DS-2P/DS-4P, and CQ arrays are
flown; the 650-Ps are on the floor.
The CH 1 Mid-Hi and CH 3 outputs drive the inner three and
outer two loudspeakers of the MSL-4 array, applying appro-
priate levels for loudspeakers directed at different distances.
The diagram shows the additional mid-hi output created by con-
necting the CH 1 Loop to the CH 3 input. Using a Y-connection
at the CH 1 input (as shown for the down-fills) accomplishes
the same signal routing. The Lo Cut and Array EQ switches
for both channels should be
in
. The Lo Cut filters eliminate
the LF rise caused by the frequency response overlap between
the MSL-4 and DS-2P/DS-4P/650-P systems. The Array EQ
filters minimize
th
e MSL-4 array’s low-mid rise.
The CH 1 DS-2 and Sub outputs drive the DS-2P/DS-4P and
650-P loudspeaker systems with the DS-2 & Sub Crossover
switch
in
. Set the MSL-4 and DS-2P/DS-4P to the same
polarity. The polarity of the 650-P depends on the height and
distance of the measurement position from the subwoofer and
flown systems.
CH 5 controls the CQ down-fill system. Since the main system
is more powerful than the down-fill system to project farther
into the venue, the main system is audible in the down-fill’s
coverage area. To insure that the loudspeakers combine properly
in the intersecting coverage area:
• Set the CQ to the opposite polarity to the MSL-4 to phase
align the mid-hi frequencies and minimize the MSL-4’s
LF down-lobe.
• Use the CH 5 Lo Cut filter to eliminate the LF rise
caused by the overlap in frequency response with the
650-P and DS-2P/DS-4P systems.
• Delay the down-fill to compensate for the propagation
delay between the down-fill and main systems in the
intersecting coverage area.
We recommend that the entire system be measured, phase-
aligned, and equalized using the SIM System II Sound Analyzer
and CP-10 Parametric Equalizer.
