User Guide

10
K
knee
A knee is a sharp bend in a curve (an EQ fre-
quency response or compressor gain curve) not
unlike the sharp bend in your leg.
L
level
Another word for signal voltage, power,
strength or volume. Audio signals are some-
times classified according to their level. Com-
monly used levels are: microphone level (-40
dBu or lower), instrument level (-20 to -10
dBu), and line level (-10 to +30 dBu).
line level
A signal whose level falls between -10 dBu and
+30 dBu.
M
main (house) speakers
The main loudspeakers for a sound reinforce-
ment system. These are usually the largest and
loudest loudspeakers, and are usually posi-
tioned so that their sound seems to come from
the area of the main stage.
mains
Short for main or house speakers in a sound rein-
forcement system.
master
A control affecting the final output of a bus on
which one or more signals are mixed. A mixer
may have several master controls, which may
be slide faders or rotary controls.
mic amp
See mic preamp.
mic level
The typical level of a signal from a microphone.
A mic level signal (usually but not always com-
ing from a microphone) is generally lower than
-30 dBu. With a very quiet source (a pin drop-
ping?) the signal can be -70 dBu or lower.
Some microphones, notably vintage or vintage-
style condenser mics, deliver a higher signal
level than this for the same sound pressure
level. A “hot” mic output level isn’t necessarily
a measure of the microphone’s quality, it’s just
an option that the designer chose.
mic pre
Short for mic preamp.
mic preamp
Short for microphone preamplifier. An ampli-
fier whose job is to bring the very low micro-
phone level signal up to line level, or in the
case of a mic preamp built into a mixer, the
mixer’s internal operating level (approximately
0 dBu).
Mic preamps often have their own volume con-
trol, called a trim control, to properly set the
gain for a particular source. Setting the mic
preamp gain correctly with the trim control is
an essential step in establishing good signal-to-
noise ratio and sufficient headroom for your
mix.
MIDI
Acronym for Musical Instrument Digital Inter-
face. MIDI is the music industry’s standard
serial communication protocol for the interface
and control of musical instruments.