Allen&Heath Xone 32 - Manual (Page 21)

XONE:32 User Guide 21
loop by removing all but one path to earth usually solves
the problem.
Equaliser (EQ) This provides cut or boost of selected
frequencies (equalisation) for tonal shaping of the sound.
This is similar to the bass and treble controls of domestic
hifi amplifiers. However, XONE:32 provides 3
independently controllable frequency bands for corrective
or effective sound shaping.
Feedback Also known as ‘howlround’ or ‘ringing’ this is
the rapidly increasing tone produced when a microphone
picks up its own signal from the speakers. It is usually a
shrill and annoying squeal that should be quickly dealt with
by repositioning the microphone or speakers, reducing mic
gain or equalising the system to notch out the offending
frequencies.
Gain This is the boost or attenuation applied to the
source signal in the channel preamp stage to match it to
the console operating level. For example, a large amount
of gain is need to match low microphone signals. It is set
using the console meters. Gain is not used for level
(volume) control.
Headroom The amount of level available expressed in
dB to handle peaks above the normal 0dB operating level.
Hz Hertz. The measurement of frequency. The audio
spectrum ranges from a low (bass) frequency of 20Hz to a
high (treble) 20kHz. Not many sound systems reproduce
the full range. Average hearing does not extend much
beyond 15kHz or so. Response is further impaired if the
ear is subjected to continual high sound pressure levels.
Highpass (HPF) A filter that attenuates frequencies
below the cut-off frequency.
Hum Apart from not knowing the words… this is the
audible noise that usually results from mains interference
pickup, earth loops, bad interconnections and induced
power supply and lighting fields. It is usually at mains
frequency (50/60Hz) or a related harmonic.
Impedance (Z) A technical term for the resistance of a
signal conductor to ground. Low impedance usually refers
to microphones of 200 ohms or less, and line signals
typically less than 100 ohms. Low Z sources are less
prone to interference pickup. Inputs are usually high
impedance so that one source can connect to more than
one channel without signal loss. Note that the operating
impedance of a connection is set by the impedance of the
source, not that of the unconnected input.
Impedance balanced Refers to the type of output signal
connection. It has three conductors, two for signal and a
shield which is connected to earth. Provides interference
rejection similar to a fully balanced connection because
the two signal conductors are matched at the same
impedance. However, the drive capability is less because
the signal is carried by only one conductor.
LFO Low Frequency Oscillator. Generates a repetitive
control voltage at a user determined rate (speed) to
automatically modulate an effect such as the VCF.
Limiter A signal processor that limits the maximum level
possible by preventing the signal going over a
predetermined threshold level. This is very useful in club
installations where it is inserted between the console and
house system amplifiers to prevent the DJ exceeding the
maximum allowable volume.
Lowpass (LPF) A filter that attenuates frequencies above
the cut-off frequency.
MC Master of Ceremonies. The presenter who introduces
the performances and maintains the running order. Also
refers to a rapper who talks in time to the beat.
MiniDisc A type of low cost digital 2-track recorder that
uses a disc similar to but smaller than that used by
computers. It uses a compression algorithm and is able to
record up to 74 minutes of stereo material. It is regarded
as the modern replacement for the audio cassette
recorder. It has the added facility to label and edit tracks.
Mono A single source with no stereo content, or the left
and right stereo signals summed together as one.
Mute To turn off the signal. Transform is a mute effect.
Noise Generic term for an unwanted signal. This may be
residual electronic hiss, hum, buzz, clicks and pops, or
simply loud undesirable music.
Noise Floor This is the term for the residual electronic
noise produced by all powered audio equipment. It usually
sounds like a constant hiss, although some equipment
may suffer from residual hum as well.
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:32 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 as the listener
moves between the speakers.
Punch Performance effect popular with DJ’s. Pressing a
button next to the crossfader punches in (turns on) the
opposite track.
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