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P
PA
Acronym for Public Address. Today, people
who work with PA systems like to say they’re
working in “sound reinforcement”. See SR.
pan, pan pot
Short for panoramic potentiometer. A pan pot
is used to position (or even dynamically move)
a monaural sound source in a stereo mixing
field by adjusting the source’s volume between
the left and right channels. Our brains sense ste-
reo position by hearing this difference in loud-
ness when the sound strikes each ear, taking
into account time delay, spectrum, ambient
reverberation and other cues.
parallel mono
A mode of operation for a stereo amplifier that
routes a single input to both channels, but
combines the outputs of both channels into a
single output by strapping the positivie output
terminals together, thereby providing twice the
current of an individual output.
patchbay
A collection of usually a large number of jacks
allowing convenient access to various points in
a system’s interconnect wiring. A patchbay can
make re-routing signals very convenient with-
out having to fish around with cables in the
back of racks or consoles. See
spaghetti.
parametric EQ
A “fully” parametric EQ is an extremely power-
ful equalizer that allows smooth, continuous,
and independent control of each of the three
primary EQ parameters: frequency, gain, and
bandwidth. “Semi” parametric EQs allow con-
trol of fewer parameters, usually frequency and
gain (i.e., they have a fixed bandwidth, but vari-
able center frequency and gain).
peaking
The opposite of dipping, of course. A peak is an
EQ curve that looks like a hill, or a peak. Peak-
ing with an equalizer amplifies a band of fre-
quencies.
PFL
An acronym for Pre Fade Listen. Broadcasters
would call it cueing. Sound folks call it being
able to solo a channel with the fader down.
phantom power
A system of providing electrical power for con-
denser microphones (and some electronic
pickup devices) from the microphone input
jack. The system is called phantom because the
power is carried on standard microphone audio
wiring in a way that is “invisible” to ordinary
dynamic microphones. Mackie mixers use stan-
dard +48 volt DC power, switchable on or off.
Most quality condenser microphones are
designed to use +48 VDC phantom power.
Check the manufacturer’s recommendations.
Generally, phantom power is safe to use with
non-condenser microphones as well, especially
dynamic microphones. However, unbalanced
microphones, some electronic equipment (such
as some wireless microphone receivers) and
some ribbon microphones can short out the
phantom power and be severely damaged.
Check the manufacturer’s recommendations
and be careful!
phase
The time relationship between two signals,
expressed in degrees around a circle. 0 and 360
degrees represents an in-phase relationship –
both signals change in the same way at the
same time. Anything else is out of phase.
180 degrees out of phase is a special case which,
for a continuous waveform, means that at any
given time the two signals have the same ampli-
