Mono Mic/Line Channels; Mono Channel Insert; Input Level Setting; Low Cut Switch - Alto AMX-180 User Manual

4.1 MONO MIC/LINE CHANNELS

These are channel 1 through channel 4. You can connect balanced,
low impedance microphones or a low level signal to the XLR socket.
On the 1/4" line jack you can connect either a microphone or a line
level instrument such as synthesizers, drum machines, effect pro-
cessors or any other line level signal.
Note: You shall never connect an unbalanced microphone to the
XLR socket if you do not want to damage both the microphone and
mixer. Also, it is not possible to simultaneously use both the MIC
&LINE inputs on the same channel, use only one of them for the
appropriate source.
PHANTOM POWER +48 VOLT
It is available only to the XLR MIC sockets. Never connect a mic-
rophone when phantom power is already on.

4.2 MONO CHANNEL INSERT

Insert sockets are provided for all mono MIC channels. It can
allow you patch external signal processing devices into signal path
via a TRS connector, the signal will be taken out after the input
gain control (Trim), and sent to an external processor such as a
compressor- limiter, then returned into the same channel imme-
diately before the EQ section.
Note: Usually, insert connections require a special stereo-splitting
Y-cord to be connected, known as TRS connector (Tip Send/Ring
Return).

4.3 INPUT LEVEL SETTING

This control is provided with 2 different indication rings: one is for
the microphone and the other for the line level. When you use a
microphone you shall read the OUTSIDE ring (0 ~ 44dB), when
you use a line level instrument you shall read the INSIDE ring
(+15 ~ -30dB). For optimum operation you shall set this control in
a way that the peak LED will blink also occasionally in order to
avoid distortion on the input channel.

4.4 LOW CUT SWITCH

By pressing this button you will activate a 75Hz low frequency
filter with a slope of 18 dB per octave. You can use this facility to
reduce the hum noise caused by the mains power supply, or the
stage rumble while using a microphone.

4.5 STEREO INPUTS

These are channel 5 through channel 12. They are organized in
stereo pair and provided with 1/4" TRS sockets. Use the left
input if connect a mono input signal to the STEREO INPUT. There
is an additional MIC input jack and a TRIM control on channel 5/6.

4.6 +4dBu/-10dBV

These switches adjust the input sensitivity of the line inputs on the
stereo channels CH5~CH12. +4dBu is suitable for professional
audio devices, -10dBV is suitable for general HI-FI devices. If not
sure to use which setting, try +4dBu first, or change it to -10dBV
if the volume is too small to be satisfied.
1
2
3
4
5
6
2
MIC (MONO)
0dB
9
MIC 1
J.T. J.T.
2 1
3
BAL OR BAL OR
UNBAL UNBAL
LINE IN 1
INSERT
TRIM
+15dB +15dB -30dB LINE -30dB LINE
0dB 0dB 44dB MIC 44dB MIC
LOW CUT LOW CUT
75Hz 75Hz
18dB/Oct 18dB/Oct
LINE IN 5/6 LINE IN 7/8
J.T. J.T.
1
3
LEFT (MONO)
LEFT(MONO) LEFT(MONO)
TRIM
RIGHT RIGHT
LEVEL LEVEL
+4dBu +4dBu
44dB MIC
-10dBV -10dBV
1
2
3
4
5
6