The Mono Mic/Line Channels; Input Level Setting; Mono Channel Insert; Low-Cut Filter - Alto L-12 User Manual

4. CONTROL ELEMENTS

4.1 The mono MIC/LINE channels

These are Channel 1 through Channel 4. You can connect balanced, low im-
pedance microphones to the XLR socket. On the 1/4" phone jack you can
connect either a microphone or a line level instrument. You shall never connect
an unbalanced microphone to the XLR socket if you do not want to damage
both the Microphone and the Mixer.
48 Volt phantom power
It is available only to the XLR Mic sockets. Never plug in a microphone when
phantom power is already on. Before turning phantom power on, make sure
that all faders are all the way down. In this way you will protect your Stage
Monitors and Main Loudspeakers.

4.2 INPUT LEVEL setting

This Control is provided with 2 different indication rings: One is
for the Microphone and the other for the Line levels. When you
use a microphone you shall read the OUTSIDE ring (0-60 dB),
When you use a Line level instrument you shall read the INSIDE
ring (+15~-45 dB). 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.

4.3 Mono Channel INSERT

Insert points are provided for the Mono Mic Channels. When you
insert a TRS jack in the insert socket, the signal will be taken out
after the Input Gain Control (Trim), sent to an external processor
such as a compressor-limiter, and returned into the channel strip
immediately before the EQ section. Of course, the jacks used must
be stereo (Tip Send/Ring Return).

4.4 LOW-CUT FILTER

By pressing this button you will activate a 75 Hz low frequency filter with a slope of 18 dB per octave. You can use
this function to reduce hum and stage rumble when using microphones.
1
4
2
3
5
8
MIC 1
2
3
LINE IN 1
BAL/UNBAL
INSERT
0dB 60dB
+15dB -45dB
LOW CUT
75Hz
18dB/Oct
POWER PHANTOM
ON
OFF
1
1
3
TRIM
2
1
MIC
LINE
5
4