Specifications

17
Inductance. The property of an electrical 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.
Inductor. A device designed primarily to introduce induc-
tance into an electrical circuit. Sometimes called a choke
or coil.
Linearity.Theextenttowhichanysignalhandlingprocess
is accomplished without amplitude distortion.
Midrange.Themiddlefrequencieswheretheearisthe
most sensitive.
NAC. The abbreviation for natural ambience compensation.
Passive crossover.Usesnoactivecomponents(transistors,
ICs,tubes)andneedsnopowersupply(AC,DC,battery)
to operate. The crossover in a typical loudspeaker is of the
passive variety. Passive crossovers consist of capacitors,
inductors and resistors.
Phase. The amount by which one sine wave leads or lags
asecondwaveofthesamefrequency.Thedifferenceis
described by the term phase angle. Sine waves in phase
reinforceeachother;thoseoutofphasecancel.
Pink noise. A random noise used in measurements, as it
has the same amount of energy in each octave.
Polarity. The condition of being positive or negative with
respect to some reference point or object.
RMS.Abbreviationforrootmeansquare.Theeffectivevalue
ofagivenwaveformisitsRMSvalue.Acousticpoweris
proportionaltothesquareoftheRMSsoundpressure.
Resistance. That property of a conductor by which it opposes
the flow of electric current, resulting in the generation of
heatintheconductingmaterial,usuallyexpressedinohms.
Resistor. A device used in a circuit to provide resistance.
Resonance. The effect produced when the natural
vibrationfrequencyofabodyisgreatlyamplifiedby
reinforcing vibrations at the same or nearly the same fre-
quencyfromanotherbody.
Sensitivity. The volume of sound delivered for a given
electrical input.
Stator.Thefixedpartformingthereferenceforthemoving
diaphragm in a planar speaker.
THD.Theabbreviationfortotalharmonicdistortion.(See
Distortion)
TIM. The abbreviation for transient intermodulation distortion.
Transducer. Any of various devices that transmit energy
from one system to another, sometimes one that converts
the energy in form. Loudspeaker transducers convert elec-
trical energy into mechanical motion.
Transient. Applies to that which lasts or stays but a short
time. A change from one steady-state condition to another.
Tweeter. A small drive unit designed to reproduce only
highfrequencies.
Wavelength. The distance measured in the direction of
progression of a wave, from any given point character-
izedbythesamephase.
White noise. A random noise used in measurements, as it
hasthesameamountofenergyateachfrequency.
Woofer.Adriveunitoperatinginthebassfrequenciesonly.
Drive units in two-way systems are not true woofers but are
more accurately described as being mid/bass drivers.
GlossaryofAudioTerms17