Glossary

AnnotationNameDescription
InchesUnit of measurement of distance.
$DollarsUnit of measurement of United States currency.
%PercentDenotes a portion of the whole.
AAmpsUnit of measurement of electrical current.
AvArea of VentUnit denoting the cross-section of a waveguide.
BlScalar Motor StrengthA product of the magnetic force and coil length.
Bl²/ReVector Motor StrengthA product of the magnetic force and coil length adjusted for resistance.
ChChannelIndividual signal path.
cmCentimetersUnit of measurement of distance.
cm²Square CentimetersUnit of measurement of surface area.
CmsSuspension ComplianceMechanical resistance of the spider and surround.
cu ftCubic FeetUnit of measurement of volume.
D2Dual 2 OhmDenotes a driver with two 2 Ohm voice coils.
D4Dual 4 OhmDenotes a driver with two 4 Ohm voice coils.
dBDecibelsUnit of measurement of signal strength / sensitivity.
DiaDiameterMeasurement across a circle.
DSPDigital Signal ProcessorDenotes a process (or a processor) for modifying signal.
EBPEfficiency Bandwidth ProductDenotes the trade-off between a driver’s efficiency and bandwidth.
F33 dB Down FrequencyA point at which the sensitivity is down by 3 dB.
FbSystem Resonant FrequencyThe fundamental resonant frequency of a vented system.
FcSealed Driver FsDriver’s natural resonance under the influence of a sealed chamber.
FsFree-Air ResonanceDriver’s natural resonance without the influence of an enclosure.
ftFeetUnit of measurement of distance.
gGramsUnit of measurement of mass.
HzHertzUnit denoting cycles per second.
inInchesUnit of measurement of distance.
kgKilogramsUnit of measurement of mass.
kg/sKilograms per SecondUnit of mass flow rate describing resistive losses.
kHzKilohertzUnit denoting thousands of cycles per second.
lLitersUnit of measurement of volume.
lbPoundsUnit of measurement of mass.
LeInductanceResistance to a change in electrical force.
LvLength of VentAxial length of a waveguide.
mHMillihenriesUnit of measurement of inductance.
mmMillimetersUnit of measurement of distance.
mm/NMillimeters per NewtonUnit of measurement of pressure.
MmsMoving MassThe combined physical mass of the driver’s moving parts plus air mass.
N/ANot ApplicableDenotes no available value or answer.
N²/WVector Motor StrengthUnit denoting magnetic force and coil length adjusted for resistance.
noHalf-Space EfficiencyCalculated reference efficiency of the driver in half-space.
QesElectrical QualityDescribes the driver’s electrical damping properties.
QmsMechanical QualityDescribes the driver’s electrical mechanical properties.
QtcTotal Enclosure QDescribes the driver’s and the enclosure’s combined damping properties.
QtsElectromechanical QualityDescribes the driver’s electro-mechanical damping properties.
ReResistanceDescribes the DC resistance of the driver’s voice coil.
RmsResistive LossesDescribes the mechanical losses of the suspension including air mass.
S4Single 4 OhmDenotes a driver with a single 4 Ohm voice coil.
SdPiston AreaDescribes the surface area of the radiating portion of the driver.
SPLSound Pressure LevelUnit of amplitude.
TmTesla MetersUnit of magnetic flux density.
USAUnited States of AmericaA country.
VasEquivalent Air ComplianceAir equivelant to the force exerted by the driver’s mechanical suspension.
VbChamber VolumeVolume of the driver’s compression chamber.
WWattsUnit of measurement of electrical power.
XmaxMaximum ExcursionDriver’s peak linear excursion.
ZNominal ImpedanceNominal impedance of a driver.
ΩOhmsUnit of measurement of electrical resistance.