40
equals the center frequency divided by the dif-
ference between the upper and lower –3dB
frequencies. A peaking EQ centered at 10kHz
whose –3dB points are 7.5kHz and 12.5kHz has
a Q of 2.
RCA phono jack—
or
RCA jack
or
phono jack
An RCA phono jack is an inexpensive con-
nector (female) introduced by RCA and
originally used to connect phonographs to radio
receivers and phono preamplifiers. The phono
jack was (and still is) widely used on consumer
stereo equipment and video equipment but was
quietly fading into obscurity in the professional
and semi-professional sound world. Then phono
jacks began cropping up in early project-studio
multitrack recorders, which (unfortunately)
gave them a new lease on life. Since so many
stereo recorders are fitted with them, we de-
cided we’d have to put a couple on our mixers
for your convenience. But make no mistake: the
only thing that the phono jack (or plug) has
going for it is low cost.
RCA phono plug
The male counterpart to an RCA phono
jack. See above.
regeneration
Also called recirculation. A delay effect cre-
ated by feeding the output of a delay back into
itself to cause a delay of the delay of the delay.
You can do it right on the front panel of many
effects units, or you can route the delay return
back into itself on your mixer. Can be a great
deal of fun at parties.
return
A return is a mixer line input dedicated to
the task of returning processed or added
sound from reverb, echo and other effects de-
vices. Depending on the internal routing of
your mixer and your own inclination, you could
use returns as additional line inputs, or you
could route your reverb outputs to ordinary
line inputs rather than the returns.
reverberation, reverb
The sound remaining in a room after the
source of sound is stopped. It’s what you hear
in a large tiled room immediately after you’ve
clapped your hands. Reverberation and echo
are terms that can be used interchangeably,
but in audio parlance a distinction is usually
made: reverberation is considered to be a dif-
fuse, continuously smooth decay of sound,
whereas echo is a distinct, recognizable repeti-
tion of a word, note, phrase or sound.
Reverberation and echo can be added in sound
mixing by sending the original sound to an
electronic (or electronic/acoustic) system that
mimics natural reverberation, or worse. The
added reverb is returned to the blend through
additional mixer inputs. Highly reverberant
rooms are called live; rooms with very little re-
verberation are called dead. A sound source
without added reverb is dry; one with reverb or
echo added is wet.
RMS
An acronym for root mean square, a conven-
tional way to measure AC voltage and audio
signal voltage. Most AC voltmeters are cali-
brated to read RMS volts. Other conventions
include average volts, peak volts and peak-to-
peak volts.
send
A term used to describe a secondary mix and
output of the input signals, typically used for
foldback monitors, headphone monitors or effects
devices. Mackie mixers call it an Aux Send.
shelving
A term used to describe the shape of an
equalizer’s frequency response. A shelving
equalizer’s response begins to rise (or fall) at
some frequency and continues to fall (or rise)
until it reaches the shelf frequency, at which
point the response curve flattens out and re-
mains flat to the limits of audibility. If you were
to graph the response, it would look like a shelf.
Or more like a shelf than a hiking boot. The EQ
controls on your stereo are usually shelving
equalizers. See also
peaking
and
dipping.
slap, slapback
A single-delay echo without any repeats.
Also see
echo.
solo
Italian for alone. In audio mixers, a solo cir-
cuit allows the engineer to listen to individual
channels, buses or other circuits singly or in
combination with other soloed signals.
SR
An acronym for Sound Reinforcement,
which refers to a system of amplifying acoustic
and electronic sounds from a performance or
speech so that a large audience can hear
clearly. Or, in popular music, so that a large au-
dience can be excited, stunned or even
partially deafened by the tremendous amplifi-
cation. Means essentially the same thing as PA
(Public Address).
