MartinLogan ElectroMotion® ESL X Manuale Proprietario

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pushing an amplifier beyond its capabilities. The flat-
topped signal has high levels of harmonic distortion 
which creates heat in a loudspeaker and is the major 
cause of loudspeaker component failure. 
CLS. The abbreviation for curvilinear line ESL.
Crossover. An electrical circuit that divides a full 
bandwidth signal into the desired frequency bands 
for the loudspeaker components. 
dB (decibel).  A numerical expression of the 
relative loudness of a sound. The difference in 
decibels between two sounds is ten times the Base 
10 logarithm of the ratio of their power levels.
DC. Abbreviation for direct current. 
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. 
 
Diaphragm. A thin flexible membrane or cone 
that vibrates in response to electrical signals to 
produce sound waves. 
 
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. 
 
Driver. See transducer. 
 
Dynamic  Range.  The range between the 
quietest and the loudest sounds a device can 
handle (often quoted in dB). 
 
Efficiency.  The acoustic power delivered for 
a given electrical input. Often expressed as 
decibels/watt/meter (dB/w/m). 
ESL. The abbreviation for electrostatic loudspeaker. 
Headroom. The difference, in decibels, between 
the peak and RMS levels in program material. 
Hybrid.  A product created by the marriage 
of two different technologies. Meant here as 
the combination of a dynamic woofer with an 
electrostatic transducer. 
 
Hz (Hertz). Unit of frequency equivalent to the 
number of cycles per second. 
 
Imaging. To make a representation or imitation 
of the original sonic event.
Impedance.  The total opposition offered by 
an electric circuit to the flow of an alternating 
current of a single frequency. It is a combination 
of resistance and reactance and is measured in 
ohms. Remember that a speaker’s impedance 
changes with frequency, it is not a constant value.
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 inductance 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. 
 
Passive crossover. Uses no active components 
(transistors, IC’s, tubes) and needs no power 
supply (AC, DC, battery) to operate. The crossover 
in a typical loudspeaker is of the passive variety.