Speaker Connections
f Speaker receptacle (see figure 2) — Connect
the speakers to the speaker receptacle using the
2-pole, 5 mm screw-lock captive screw connector
(MPA 401-100V shown at right).
NOTES:
• The mono audio speaker receptacle may be labeled in one of two ways (see
the diagrams above). The wiring and function are the same whichever way the
product is labeled.
• The MPA 401 amplifier sums the left and right signals from both the TRS and
RCA inputs to form Sum 1. Sum 1 is then weighted. At the same time, the
amplifier sums the left and right signals from the captive screw input to form
Sum 2. Sum 1 and Sum 2 are then summed together to form a single mono
signal. See figure 6 below for more details.
• The captive screw, RCA and TRS inputs are buffered.
Amp Stage
+
+
RCA
R
L
R
L
Captive
Screw
+
+
R
L
+
-
+
-
+
+
Sum 1
Sum 2
3.5 mm
TRS
Figure 6. Summing MPA 410 input signals to form a single mono output signal
The MPA401-70V provides up to 40 W for a 70 V line distributed sound system; the
MPA401-100V provides up to 40 W for a 100 V line distributed sound system.
See the attention and the note on page 6 for important information about
connecting wires to captive screw connectors.
ATTENTION: Do not ground or short the speaker outputs as this will damage
the amplifier.
CLASS 2 WIRING
100V OUTPUT
100V
MPA 401-70V and MPA 401-100V • Rear Panel and Cabling 9
