ALLEN & HEATH XONE 92 User Manual page 33

Omni-directional The response of a microphone
which picks up sounds equally all round. Not suited
to live vocal applications as they are more prone to
feed back.
Pan Panoramic. A control that adjusts the balance
of the signal in the left and right speakers.
Peak Meter A type of signal meter that has a very
fast attack and slower release. This picks up the
fast signal transients and holds them long enough
for the operator to see the activity on the display.
These meters typically use led (light emitting diode)
displays.
Phantom Power The DC voltage required by
certain microphones to power the capsule. These
are usually sensitive studio grade mics not suited to
DJ mixing. The power is provided by the console
using the two signal conductors in the balanced
connection. There is no provision on XONE for this
type of microphone.
Phono Abbreviation for phonograph as in
'turntable'. Usually means RIAA equipped input
when marked on console inputs. Can also refer to
the RCA 'phono' type pin jack connector found on
turntables, CDs and much domestic equipment.
Polarity Sometimes referred to as 'phase' this is
the + / - sense of a balanced signal or loudspeaker
connection. Reversed polarity should be avoided
and checked for as it can cause uncomfortable
phasing effects between speakers.
Resonance Applied to the filters this is the effect
of accentuating frequencies around the cut-off point
to produce subtle or dramatic phasing effects.
RIAA Record Industry of America Association,
responsible for the long established equalisation
standard that is applied to the signal produced by a
turntable cartridge. Due to the physics of vinyl
reproduction the needle produces a reasonable high
frequency signal but much less low frequency. An
RIAA pre-amplifier compensates for this by
inversely attenuating the high and boosting the low
frequencies.
Reverberation The way in which sound reflects
and bounces around the room after the source is
removed. This depends on the size and shape of
the room as well as the materials such as carpets,
curtains and clothing that absorb certain
frequencies.
Reverb Effect This is a signal processor that
connects to the console to artificially simulate the
reverb effect. Parameters such as decay time,
diffusion and amount of reverb can be controlled.
Typically selected sounds are sent to the processor
by turning up the channel post-fade aux sends. The
processed (wet) signal is returned to the mix
through a channel where it adds to the direct (dry)
signal routed from the channel fader.
RPM Revolutions Per Minute. The measurement
of turntable speed.
XONE:92 User Guide
Sampler Another performance effect popular with
DJs. The channel signal is sent to a digital
processor that samples (stores) a short duration of
sound. The output is returned through a channel
and replayed by pressing a trigger. Many samplers
provide creative effects such as repeat and reverse.
Scratch Mixing The art of rhythmically rocking a
record back and forward on a turntable, to repeat a
certain sound, a vocal or tone, at the same time
operating the cross-fader to create a syncopated
"wah wah" chirp added over a bass heavy back
beat.
Signal-to-Noise Ratio (SN) This is the difference
expressed in dB between the normal 0dB operating
level and the residual noise floor. It represents how
far above the equipment hiss level the signal
operates. More is better.
Slipmat A fabric turntable mat positioned under
the record so that the DJ can hold it stationary ready
to let go for a fast start at the point cued.
Sound-to-Light A processor that converts an
audio signal into a control voltage that triggers
lighting effects. This produces the popular disco
effects with lights flashing in time to the beat.
Split Cue A facility to listen to the cue signal in one
ear while keeping the program in the other. Used
for matching the beat while cueing a new track.
Sub Bass A loudspeaker designed to reproduce
only very low frequency sound, typically from
around 50 to 120Hz. A crossover is used to route
only the low frequencies to the sub.
TRS Jack Refers to the 3-pole (stereo) ¼" jack
plug with Tip, Ring and Sleeve connections.
Turntable Otherwise known as a 'record deck' this
plays vinyl discs, still the most popular source for DJ
mixing. It is common for the cartridge to plug
directly into the mixing console 'phono' input which
provides the RIAA equalisation required. The
turntable usually has variable speed control so that
the DJ can synchronise the beat between tracks.
VCA Voltage Controlled Amplifier. An audio gain
element whose level is controlled by a remote DC
voltage rather than through a fader or rotary control.
VCA Crossfader Functions as an audio
crossfader but with the audio level controlled by a
DC voltage produced by the fader. This voltage can
be electronically filtered and is therefore able to
remove the clicks, scratches and drop-outs
associated with worn audio faders.
VCF Voltage Controlled Filter. An audio filter
whose cut-off frequency is controlled by a remote
DC voltage rather than a rotary or switched control.
This provides greater range and capability.
XLR The professional standard 3 pin round
connector used for microphone and other balanced
connections. Equipment female sockets are for
inputs, male for outputs.
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