Panel Layout & Function; Input Module (Channel Strip) - Mackie LM-3204 Owner's Manual

SECTION 2: PANEL LAYOUT & FUNCTION
ON THE LEFT SIDE
16
U
3 Most of the LM-3204 front panel (four-fifths,
1
O O +15 precisely) is occupied by the 16 stereo, line
STEREO
U
level input modules or channel strips. Each
4
strip sports identical features, functions, knobs
2
+15
O O
MONO SHIFT
and buttons, so we'll take a close look at one
AUX
and leave it to you to extrapolate. Still with us?
HI
U
12k
ON THE RIGHT SIDE
–15 +15
U MID
The rightmost one-fifth of the LM-3204 is
2.5k
the Master Output section, featuring auxiliary
–12 +12
returns, master level controls, meters, lights
U LO
and a few other tricks.
80
GAIN
THE OFFICIAL GUIDED TOUR OF A
–15 +15
EQ
TYPICAL LM-3204 INPUT MODULE
(CHANNEL STRIP)
L L R
BALANCE
Pretty straightforward. But remember,
MUTE
these are all stereo input modules, so even
ALT 3-4
though there is only one volume control and
SOLO
one EQ section per channel strip, there are
OL
actually two audio channels, Left and Right,
CHANNEL
-20
16
routed through each strip...so each control
on an input module is a dual control, working
U
on both sides of the stereo signal.
+30dB
O O
GAIN
6
1 2 3
U U U
3 3 3
1 1 1
+15 +15 +15
O O O O O O
STEREO STEREO STEREO
U U U
4 4 4
2 2 2
+15 +15 +15
O O O O O O
SHIFT SHIFT SHIFT
MONO MONO MONO
AUX AUX AUX
HI HI HI
U U U
12k 12k 12k
–15 +15 –15 +15 –15 +15
U MID U MID U MID
2.5k 2.5k 2.5k
–12 +12 –12 +12 –12 +12
U LO U LO U LO
80 80 80
–15 +15 –15 +15 –15 +15
EQ EQ EQ
L L R L L R L L R
BALANCE BALANCE BALANCE
MUTE MUTE MUTE
ALT 3-4 ALT 3-4 ALT 3-4
SOLO SOLO SOLO
OL OL OL
CHANNEL CHANNEL CHANNEL
-20 -20 -20
1 2 3
U U U
+30dB +30dB +30dB
O O O O O O
GAIN GAIN GAIN
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.
4 5 6
U U U
3 3 3
1 1 1
+15 +15 +15
O O O O O O
STEREO STEREO STEREO
U U U
4 4 4
2 2 2
+15 +15 +15
O O O O O O
SHIFT SHIFT SHIFT
MONO MONO MONO
AUX AUX AUX
HI HI HI
U U U
12k 12k 12k
–15 +15 –15 +15 –15 +15
U MID U MID U MID
2.5k 2.5k 2.5k
–12 +12 –12 +12 –12 +12
U LO U LO U LO
80 80 80
–15 +15 –15 +15 –15 +15
EQ EQ EQ
L L R L L R L L R
BALANCE BALANCE BALANCE
MUTE MUTE MUTE
ALT 3-4 ALT 3-4 ALT 3-4
SOLO SOLO SOLO
OL OL OL
CHANNEL CHANNEL CHANNEL
-20 -20 -20
4 5 6
U U U
+30dB +30dB +30dB
O O O O O O
GAIN GAIN GAIN
7 8 9
U U U
3 3 3
1 1 1
+15 +15 +15
O O O O O O
STEREO STEREO STEREO
U U U
4 4 4
2 2 2
+15 +15 +15
O O O O O O
SHIFT SHIFT SHIFT
MONO MONO MONO
AUX AUX AUX
HI HI HI
U U U
12k 12k 12k
–15 +15 –15 +15 –15 +15
U MID U MID U MID
2.5k 2.5k 2.5k
–12 +12 –12 +12 –12 +12
U LO U LO U LO
80 80 80
–15 +15 –15 +15 –15 +15
EQ EQ EQ
L L R L L R L L R
BALANCE BALANCE BALANCE
MUTE MUTE MUTE
ALT 3-4 ALT 3-4 ALT 3-4
SOLO SOLO SOLO
OL OL OL
CHANNEL CHANNEL CHANNEL
-20 -20 -20
7 8 9
U U U
+30dB +30dB +30dB
O O O O O O
GAIN GAIN GAIN
U
1
+15
O O
STEREO
U
2
+15
O O
MONO
AUX
U
–15 +15
U
–12 +12
U
–15 +15
EQ
L L
BALANC
MUTE
ALT 3-4
SOLO
CHANNEL
10
U
O O
GAIN