Biamp MCA Series - Manual (Page 7)

7
REAR PANEL
HPF
These DIP switches provide High-Pass Filters for the input channels. High-Pass Filters are used
to eliminate unnecessary lower frequencies (12dB/octave @ 125Hz) for speech and distributed
speaker applications. From the factory, the High-Pass Filters are bypassed (switches up). To assign
a High-Pass Filter on an input channel, move the switch to the down position.
CAUTION: To avoid output fault conditions, High-Pass Filters must be assigned on channels driving
25/70/100 Volt speaker systems (see Output below). Also, any other system equalization affecting
frequencies below 125 Hz should remain flat or be used as cut-only.
Bridge
These DIP switches allow adjacent channels to Bridge together in pairs, for a higher, combined
output power (see Bridging on pg. 9). Bridge disables the even numbered input, and applies
the odd numbered input signal to both amplifier channels. From the factory, Bridge is bypassed
(switches up). To assign Bridge to a pair of channels, move the switch to the down position.
Output
These screw terminals provide the speaker outputs from the channels. Connect the positive
speaker line to the (+) terminal and the negative speaker line to the (-) terminal of the channel
being used. The minimum speaker load on an individual channel is 4 ohms.
NOTE: When using a pair of channels in ‘bridged’ mode (see Bridge above), connect the positive
speaker line to the (+) terminal of the odd numbered channel and the negative speaker line to
the (+) terminal of the even numbered channel. The minimum speaker load for a bridged output
is 8 ohms. Output transformers for 25/70/100 Volt speaker systems are available as an option
(installation instructions are included with the output transformers).
Transformers (by model) are as follows:
TDT50 = MCA 8050 individual channels (50 Watts)
TDT100 = MCA 8050 bridged channels (100 Watts)
TDT150 = MCA 8150 individual channels (150 Watts)
TDT300 = MCA 8150 bridged channels (300 Watts)
AC Power Entrance
The switch applies AC power to the unit. The receptacle accepts the detachable AC Power Cord. The
AC Power Cord is for connection to three-prong grounded AC outlets.
CAUTION: Do not remove or defeat the ground prong on the AC Power Cord, as this constitutes a
shock hazard.