Explanatory Note on Specifications
29
Among the final pages of this manual (respectively attachment) you will find the specifications of your
loudspeaker
Specifications include:
-
Dimensions height x width x depth (in mm)
-
Weight (in kg)
-
Driver units: number and type of drivers
-
Nominal (sine) power (in watts)
-
Peak (pulse) power (in watts)
-
Frequency range (in hertz)
-
Sensitivity (in dB/W/m and in dB/2.83Vm)
-
Nominal impedance (in ohms)
-
Minimum impedance (in ohms at hertz)
-
Recommended amplifier power (in watts/channel)
-
Mains voltage
-
Power consumption, StandBy
-
Max. power consumption
-
Max. amplifier power
-
S/N (A-weighted)
-
Input sensivity
-
Input impedance
Dimensions
refer to the outer dimensions of the loudspeakers.
Likewise the
Weight
gives information on the net weight of the loudspeaker. Because of tolerances
among the basic materials and rate of humidity, this value may vary by 10% typically.
Drive Units
give information on the number and type of drivers of a loudspeaker.
The
Nominal Power
of a loudspeaker describes how much electric power may be supplied to the loud-
speaker during a long period of time without damaging the loudspeaker through overheating of the driv-
ers. To determine the nominal power, a statistical mixture of different frequencies with different vol-
umes is used as electric signal. This "composite signal" is selected so as to correspond on average to
the spectral distribution of different kinds of music. Thus the total power supplied to the speaker in the
determination of the nominal power is distributed to all the drive units at a particular ratio. If the electric
power corresponding to the nominal power were delivered to a single driver, it would normally be de-
stroyed.
The
Peak Power
defines the short-time power handling of a loudspeaker e.g. with respect to music
pulses. The destruction of a loudspeaker by exceeding the peak power is mostly caused by mechanical
damages of the drivers, e.g. increased deflection of the diaphragm.
The
Frequency Range
of a loudspeaker is defined by the upper and lower cutoff frequencies of the
SPL frequency response. At the cut-off frequencies the sound pressure level decreases by 8dB (factor
2.5) as compared to the midrange. Given a standard domestic room, the effective lower cutoff fre-
quency may deviate from standard values due to room resonances.
