Line Inputs; Low Cut; Trim - Mackie 1402 VLZ Owner's Manual

LINE INPUTS (Channels 1–6)
These six line inputs share circuitry (but
not phantom power) with the mic preamps,
and can be driven by balanced or unbalanced
sources at almost any level. You can use these
inputs for virtually any signal you'll come
across, from instrument levels as low as –30dB
to operating levels of –10dBV to
+4dBu, since there is 30dB more gain available
than on Channels 7–14. To learn how signals
are routed from these inputs: .
To connect balanced lines to these inputs,
use a 1 ⁄ " Tip-Ring-Sleeve (TRS) plug, the type
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found on stereo headphones:
RING
Tip = Positive (+ or hot)
Ring = Negative (– or cold)
Sleeve = Shield or ground
To connect unbalanced lines to these in-
puts, use a 1 ⁄ " mono (TS) phone plug or
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standard instrument cable:
Tip = Signal
Sleeve = Ground
Line inputs 1–6 are a good place to connect
older instruments that need more gain. You
can correct weak levels by adjusting the corre-
sponding channel's TRIM control
LOW CUT (Channels 1–6)
The LOW CUT switch, often referred to as a
High Pass Filter (all depends on how you look
at it), cuts bass frequencies below 75Hz at a
rate of 18dB per octave.
+15
+10
+5
0
–5
–10
–15
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Hz Hz Hz Hz Hz

Low Cut

earthquakes. These aside, there isn't much
down there that you want to hear, and filtering
it out makes the low stuff you do want much
more crisp and tasty. Not only that, but LOW
CUT can help reduce the possibility of feed-
back in live situations and it helps to conserve
the amplifier power.
tion is that it actually adds flexibility during
live performances. With the addition of LOW
CUT, you can safely use LOW equalization on
vocals
really benefit voices. Trouble is, adding LOW
EQ also boosts stage rumble,
mic handling clunks and
breath pops. LOW CUT re-
moves all those problems so
SLEEVE SLEEVE RING TIP
you can add low EQ without
losing a woofer.
TIP
RING
tion of LOW EQ
TIP
SLEEVE
CUT looks like in terms of
frequency curves.
Setting Procedure .
and line inputs connected to Channels 1
SLEEVE SLEEVE TIP
through 6. This allows signals from the outside
world to be adjusted to optimal internal oper-
TIP
TIP ating levels.
SLEEVE
jack, there will be 10dB of gain with the knob
fully down, ramping to 60dB of gain fully up.
tenuation fully down and 40dB of gain fully up,
with a "U" (unity gain) mark at 9:00.
.
when you are inserting a signal that is very hot,
or when you want to add a lot of EQ gain, or
both. Without this "virtual pad," a scenario like
that might lead to channel clipping.
We recommend
the line inputs on channels 7–14. If the sound
that you use LOW
source is a "–10" device, engage this switch. If
CUT on every micro-
you are unsure, leave the switch up and per-
phone application
form the Level Setting Procedure ,
except kick drum,
substituting this switch for the TRIM knob and
bass guitar, bassy
then setting the switch to the appropriate gain
synth patches, or re-
setting.
cordings of
Another way to consider LOW CUT's func-
. Many times, bass shelving EQ can
Here's what the combina-
and LOW
TRIM (Channels 1–6)
If you haven't already, please read the Level
TRIM adjusts the input sensitivity of the mic
If the signal originates through the XLR
Through the 1 ⁄ " input, there is 10dB of at-
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This 10dB of attenuation can be very handy
+4 / –10 (Channels 7–14)
This switch adjusts the input sensitivity of
+15
+10
+5
0
–5
–10
–15
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Hz Hz Hz Hz Hz
Low Cut with Low EQ
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