On the left side, On the right side, The gain control – MACKIE LM-3204 User Manual
Page 6
6
SECTION 2: PANEL LAYOUT & FUNCTION
ON THE LEFT SIDE
Most of the LM-3204 front panel (four-fifths,
precisely) is occupied by the 16 stereo, line
level input modules or channel strips. Each
strip sports identical features, functions, knobs
and buttons, so we’ll take a close look at one
and leave it to you to extrapolate. Still with us?
ON THE RIGHT SIDE
The rightmost one-fifth of the LM-3204 is
the Master Output section, featuring auxiliary
returns, master level controls, meters, lights
and a few other tricks.
THE OFFICIAL GUIDED TOUR OF A
TYPICAL LM-3204 INPUT MODULE
(CHANNEL STRIP)
Pretty straightforward. But remember,
these are all stereo input modules, so even
though there is only one volume control and
one EQ section per channel strip, there are
actually two audio channels, Left and Right,
routed through each strip…so each control
on an input module is a dual control, working
on both sides of the stereo signal.
THE GAIN CONTROL
At the bottom of each strip is the white Gain
knob, which is a stereo gain control for that
channel’s signal. In the time-honored Mackie
tradition, the Gain control has a tremendous
range, from off at the
“ ”
mark to unity (no gain
or loss of gain) to a 30dB increase in signal level
when fully clockwise providing 15dB of gain
above unity. This range allows the LM-3204 to
easily handle a wide range of “line level” inputs,
from professional +4dBu and +8dBu levels all
the way down to consumer and semi-pro-type –
10dBV levels and lower.
The “U” mark at the top
center the Gain control’s
arc of travel stands for
“Unity Gain.” It’s the point
at which no level is added
to or subtracted from the input signal. With
the input Gain control and Left/Right master
gain controls set at “U,” a –10dBV signal at
the input jacks of the LM-3204 is still –10 at
the output jacks. Likewise, a +4dBu signal
comes in at +4 and goes out at +4.
U
+30dB
O
O
BALANCE
L
–15
+15
U
–12
+12
U
2
+15
O
O
U
–15
+15
U
1
+15
O
O
U
16
SHIFT
-20
OL
4
3
12k
STEREO
MONO
HI
80
LO
2.5k
MID
EQ
SOLO
AUX
L
R
16
CHANNEL
MUTE
ALT 3-4
GAIN
GAIN
U
+30dB
O
O
BALANCE
L
–15
+15
U
–12
+12
U
2
+15
O
O
U
–15
+15
U
1
+15
O
O
U
1
SHIFT
-20
OL
4
3
12k
STEREO
MONO
HI
80
LO
2.5k
MID
EQ
SOLO
AUX
L
R
U
+30dB
O
O
BALANCE
L
–15
+15
U
–12
+12
U
2
+15
O
O
U
–15
+15
U
1
+15
O
O
U
2
SHIFT
-20
OL
4
3
12k
STEREO
MONO
HI
80
LO
2.5k
MID
EQ
SOLO
AUX
L
R
U
+30dB
O
O
BALANCE
L
–15
+15
U
–12
+12
U
2
+15
O
O
U
–15
+15
U
1
+15
O
O
U
3
SHIFT
-20
OL
4
3
12k
STEREO
MONO
HI
80
LO
2.5k
MID
EQ
SOLO
AUX
L
R
U
+30dB
O
O
BALANCE
L
–15
+15
U
–12
+12
U
2
+15
O
O
U
–15
+15
U
1
+15
O
O
U
4
SHIFT
-20
OL
4
3
12k
STEREO
MONO
HI
80
LO
2.5k
MID
EQ
SOLO
AUX
L
R
U
+30dB
O
O
BALANCE
L
–15
+15
U
–12
+12
U
2
+15
O
O
U
–15
+15
U
1
+15
O
O
U
5
SHIFT
-20
OL
4
3
12k
STEREO
MONO
HI
80
LO
2.5k
MID
EQ
SOLO
AUX
L
R
U
+30dB
O
O
BALANCE
L
–15
+15
U
–12
+12
U
2
+15
O
O
U
–15
+15
U
1
+15
O
O
U
6
SHIFT
-20
OL
4
3
12k
STEREO
MONO
HI
80
LO
2.5k
MID
EQ
SOLO
AUX
L
R
U
+30dB
O
O
BALANCE
L
–15
+15
U
–12
+12
U
2
+15
O
O
U
–15
+15
U
1
+15
O
O
U
7
SHIFT
-20
OL
4
3
12k
STEREO
MONO
HI
80
LO
2.5k
MID
EQ
SOLO
AUX
L
R
U
+30dB
O
O
BALANCE
L
–15
+15
U
–12
+12
U
2
+15
O
O
U
–15
+15
U
1
+15
O
O
U
8
SHIFT
-20
OL
4
3
12k
STEREO
MONO
HI
80
LO
2.5k
MID
EQ
SOLO
AUX
L
R
U
+30dB
O
O
BALANCE
L
–15
+15
U
–12
+12
U
2
+15
O
O
U
–15
+15
U
1
+15
O
O
U
9
SHIFT
-20
OL
4
3
12k
STEREO
MONO
HI
80
LO
2.5k
MID
EQ
SOLO
AUX
L
R
U
O
O
BALANCE
L
–15
+15
U
–12
+12
U
2
+15
O
O
U
–15
+15
U
1
+15
O
O
U
STEREO
MONO
EQ
SOLO
AUX
L
1
CHANNEL
2
CHANNEL
3
CHANNEL
4
CHANNEL
5
CHANNEL
6
CHANNEL
7
CHANNEL
8
CHANNEL
9
CHANNEL
10
CHANNEL
MUTE
ALT 3-4
MUTE
ALT 3-4
MUTE
ALT 3-4
MUTE
ALT 3-4
MUTE
ALT 3-4
MUTE
ALT 3-4
MUTE
ALT 3-4
MUTE
ALT 3-4
MUTE
ALT 3-4
MUTE
ALT 3-4
GAIN
GAIN
GAIN
GAIN
GAIN
GAIN
GAIN
GAIN
GAIN
GAIN