Master Controls; Phantom Power Switch; Power Led; Meters - Mackie ProFX12 Owner's Manual

STEREO GRAPHIC EQ
37
15
10
5
0
5
10
15
125 250 500 1K
38
MAIN MIX
MON
FX PRESETS
49
01 BRIGHT ROOM
02 WARM LOUNGE
03 SMALL STAGE
04 WARM THEATER
05 WARM HALL
06 CONCERT HALL
50
07 PLATE REVERB
08 CATHEDRAL
09 CHORUS
10 CHORUS + REV
PRESETS
11 DOUBLER
12 TAPE SLAP
MUTE
13 DELAY 1 (300ms)
14 DELAY 2 (380ms)
53
15 DELAY 3 (480ms)
16 REVERB + DLY (250ms)
U U
52 OL 54
+15 +15
O O
O O
FX MASTER
FX TO MON
43 44
MUTE
OL
ST RTN FX RTN
dB dB
10 10
5 5
U U
5 5
45 46
10 10
20 20
30 30
40 40
50 50
60 60
O O O O
32
15
48V
10
PHANTOM
5
POWER
0
33
5
POWER
10
MAIN
15

METERS

2K 4K 8K
0dB=0dBu
OL
39
EQ IN
15
BYPASS
10
6
3
34
USB
0
2
4
U
7
40
10
20
30
+20
O O
L
INPUT LEVEL
35
41
51
BREAK
USB THRU
(MUTES ALL CHANNELS)
U
42 36
MAX O O
O O
PHONES TAPE LEVEL
MAIN
MON
dB dB
10 10
5 5
U U
5 5
47 48
10 10
20 20
30 30
40 40
50 50
60 60
O O O O

Master Controls

32. PHANTOM POWER SWITCH

If your microphones need phantom power, press in
this switch to add phantom power to all the XLR mi-
crophone inputs of the mixer. This lets the mixer send
low-current DC voltage to the mic's electronics through
the same wires that carry audio. The LED will turn on as
a reminder that phantom power is engaged.
Most modern professional condenser mics require
phantom power. Semi-pro condenser mics often have
batteries to accomplish the same thing. "Phantom" owes
its name to an ability to be "unseen" by dynamic mics
(Shure SM57/SM58, for instance), which don't need
external power and aren't affected by it anyway.
R
Never plug single-ended (unbalanced) micro-
phones, or ribbon microphones into the mic
input jacks if phantom power is on. Do not
plug instrument outputs into the mic input jacks with
phantom power on, unless you know for certain it is safe
to do so.
+20

33. POWER LED

This LED comes on when the mixer is plugged into
the AC mains supply, and the rear panel power switch
[3] is on.
If the LED does not turn on, make sure the AC power
is live, both ends of the power cord are correctly in-
serted, your electricity bill has been paid, and the lights
in town are on.
If you suspect the fuse is blown, disconnect
the power cord before removing and inspect-
ing the fuse located below the AC input.
34. METERS
These meters have 2 columns of 12 LEDs each, with
dB markings from –30 to +15, and OL (overload at +20
dBu). They indicate the stereo signal strength of the
main mix after the main fader [48].
Typically, you want to see these meters bouncing
between the "0" and the "+3" LEDs. It is okay if the OL
LEDs light occasionally, but if they light frequently or
continuously, turn down the main fader until they blink
occasionally or not at all.
Remember, audio meters are just tools to help assure
you that your levels are "in the ballpark." You don't have
to stare at them (unless you want to).
Owner's Manual
21