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Quest User's Manual
Glossary
ACAC
ACAC
AC. Abbreviation for alternating
current.
Active crossoverActive crossover
Active crossoverActive crossover
Active crossover. Uses active
devices (transistors, IC’s,
tubes) and some form of power
supply to operate.
AmplitudeAmplitude
AmplitudeAmplitude
Amplitude. The extreme range of a
signal. Usually measured from
the average to the extreme.
ArcArc
ArcArc
Arc. The visible sparks generated by
an electrical discharge.
BassBass
BassBass
Bass. The lowest frequencies of
sound.
Bi-AmplificationBi-Amplification
Bi-AmplificationBi-Amplification
Bi-Amplification. Uses an electronic
crossover or line-level passive
crossover and separate power
amplifiers for the high and low
frequency loudspeaker drivers.
CapacitanceCapacitance
CapacitanceCapacitance
Capacitance. That property of a
capacitor which determines how
much charge can be stored in it
for a given potential difference
between its terminals, measured
in farads, by the ratio of the
charge stored to the potential
difference.
CapacitorCapacitor
CapacitorCapacitor
Capacitor. A device consisting of two
or more conducting plates
separated from one another by an
insulating material and used for
storing an electrical charge.
Sometimes called a condenser.
ClippingClipping
ClippingClipping
Clipping. Distortion of a signal by its
being chopped off. An overload
problem caused by pushing an
amplifier beyond its capabilities.
The flat-topped signal has high
levels of harmonic distortion
which creates heat in a loud-
speaker and is the major cause of
loudspeaker component failure.
CrossoverCrossover
CrossoverCrossover
Crossover. An electrical circuit that
divides a full bandwidth signal
into the desired frequency bands
for the loudspeaker components.
dB (decibel)dB (decibel)
dB (decibel)dB (decibel)
dB (decibel). A numerical expres-
sion of the relative loudness of a
sound. The difference in decibels
between two sounds is ten times
the common logarithm of the ratio
of their power levels.
DCDC
DCDC
DC. Abbreviation for direct current.
DiffractionDiffraction
DiffractionDiffraction
Diffraction. The breaking up of a
sound wave caused by some type
of mechanical interference such
as a cabinet edge, grill frame, or
other similar object.
DiaphragmDiaphragm
DiaphragmDiaphragm
Diaphragm. A thin flexible mem-
brane or cone that vibrates in
response to electrical signals to
produce sound waves.
DistortionDistortion
DistortionDistortion
Distortion. Usually referred to in
terms of total harmonic distortion
(THD) which is the percentage of
unwanted harmonics of the drive
signal present with the wanted
signal. Generally used to mean
any unwanted change introduced
by the device under question.
DriverDriver
DriverDriver
Driver. See transducer.
Dynamic RangeDynamic Range
Dynamic RangeDynamic Range
Dynamic Range. The range
between the quietest and the
loudest sounds a device can
handle (often quoted in dB).
EfficiencyEfficiency
EfficiencyEfficiency
Efficiency. The acoustic power
delivered for a given electrical
input. Often expressed as
decibels/watt/meter (dB/w/m).
ESLESL
ESLESL
ESL. Abbreviation for electrostatic
loudspeaker.
HeadroomHeadroom
HeadroomHeadroom
Headroom. The difference, in
decibels, between the peak and
RMS levels in program material.
HybridHybrid
HybridHybrid
Hybrid. A product created by the
marriage of two different tech-
nologies. Meant here as the
combination of a dynamic woofer
with an electrostatic transducer.
Hz (Hertz)Hz (Hertz)
Hz (Hertz)Hz (Hertz)
Hz (Hertz). Unit of frequency
equivalent to the number of
cycles per second.
ImagingImaging
ImagingImaging
Imaging. To make a representation
or imitation of the original sonic
event.
ImpedanceImpedance
ImpedanceImpedance
Impedance. The total opposition
offered by an electric circuit to the
flow of an alternating current of a
single frequency. It is a combina-
tion of resistance and reactance
and is measured in ohms.
Remember that a speaker’s
impedance changes with
frequency, it is not a constant
value.
InductanceInductance
InductanceInductance
Inductance. The property of an
electric circuit by which a varying
current in it produces a varying
magnetic field that introduces
voltages in the same circuit or in a
nearby circuit. It is measured in
henrys.
InductorInductor
InductorInductor
Inductor. A device designed prima-
rily to introduce inductance into
an electric circuit. Sometimes
called a choke or coil.
LinearityLinearity
LinearityLinearity
Linearity. The extent to which any
signal handling process is
accomplished without amplitude
distortion.