Mackie UP4121 Stereo Amplifier User Manual


 
UP4000 4
FRONT PANEL FEATURES
LOW EQ
is a shelving filter that provides 12 dB
of boost and cut below 100Hz.
HIGH EQ
is a shelving filter that provides 12 dB
of boost and cut above 10kHz.
VOLUME
is a master volume control used to
adjust the overall volume of the signal at the
POWER OUTPUTS
.
Use the
POWER
switch to turn the UP4000
Series on and off.
The
STD-BY
indicator lights when the amplifier is
in standby mode.
Note: Standby mode is disabled by default. An
internal jumper (J1 on the input board) must be
changed to enable standby mode. See "Internal
Settings" on page 8.
The
OVERLOAD
indicator lights when the
amplifier is operating in overload, a condition
generally caused by a problem on the speaker line.
When the amplifier is switched on, the
OVERLOAD
light comes on for a few seconds. This is normal
and does not indicate a problem.
The
SIGNAL
indicator lights when a signal is
present at the
POWER OUTPUTS
.
The
PEAK
indicator lights when the output signal
is approaching clipping.
The
ON
indicator lights when the UP4000 is
turned on and ready for operation.
REAR PANEL FEATURES
POWER INPUT
provides a means to connect an
external 24 VDC power supply or battery as an
alternative or backup power source. The UP4000
Series seamlessly switches to the backup supply if
there's an AC power loss. When both AC power
and 24 VDC power are connected, the DC power is
switched off.
Note: The unit is not equipped with battery charging
capability.
The
D.C. FUSE
protects the DC power input to
the amplifier circuit. Replace with the same type
fuse only.
POWER OUTPUTS
are screw-terminal
connections for connecting speakers to the 4-ohm,
25V, 50V, 70V, or 100V outputs.
WARNING: To prevent the risk of electric shock,
never touch the bare wires coming from the output
terminals of the amplifier when it is switched on.
When all connections have been made, insulate the
output terminals of the amplifier using the
protective cover provided.
Constant-Impedance Output
The total impedance of the speakers and cable
connected to the "4" constant-impedance output
should be 4 ohms. Connect the "4" terminal to
the "+" (HIGH) speaker terminal, and the "0"
terminal to the "–" (LOW) speaker terminal.
Constant-Voltage Output
In a constant-voltage system, each speaker must
be equipped with a line transformer having an
input voltage equal to that of the line (e.g., 25V,
50V, 70V, or 100V). Typically, these line trans-
formers have selectable power taps (i.e., 2.5W,
5W, 10W) for connecting to the constant-voltage
line. CAUTION: The sum of the wattage values
of the speakers must not exceed the output
power of the amplifier.
POWER
LOW
EQ
HIGH
VOLUME
PEAK
OVER LOAD
SIGNAL
ON
UP 4161 - P.A. AMPLIFIER
STD-BY
0
10
82
1
3
4
5
6
7
9
8
4
2
0
2
4
8
-10
+10
66
8
4
2
0
2
4
8
-10
+10
66