1 Scope
2 Normative references
3 Conditions for measurement
3.1 General conditions
3.2 Measuring conditions
4 Test signals
4.1 General
4.2 Sinusoidal signal
4.3 Broadband noise signal
4.4 Narrow-band noise signal
4.5 Impulsive signal
5 Acoustical environment
5.1 General
5.2 Free-field conditions
5.3 Half-space free-field conditions
5.4 Diffuse sound field conditions
5.5 Simulated free-field conditions
5.6 Half-space simulated free-field conditions
6 Unwanted acoustical and electrical noise
7 Positioning of loudspeaker and measuring microphone
7.1 Measuring distance under free-field and half-space
free-field conditions
7.2 Positioning of loudspeaker in diffuse field conditions
7.3 Positioning of loudspeaker and microphone in simulated
free-field conditions
8 Measuring equipment
9 Accuracy of the acoustical measurement
10 Mounting of loudspeakers
10.1 Mounting and acoustic loading of drive units
10.2 Mounting and acoustic loading of a loudspeaker system
11 Standard baffle and measuring enclosures
11.1 Standard baffle
11.2 Standard measuring enclosures
12 Preconditioning
13 Type description
13.1 General
13.2 Loudspeaker drive units
13.3 Loudspeaker system
14 Marking of terminals and controls
15 Reference plane, reference point and reference axis
15.1 Reference plane - characteristic to be specified
15.2 Reference point - characteristic to be specified
15.3 Reference axis - characteristic to be specified
16 Impedance and derivative characteristics
16.1 Rated impedance - characteristic to be specified
16.2 Impedance curve
16.3 Total Q-factor (Q[t])
16.4 Equivalent air volume of a loudspeaker drive unit
compliance (v[as])
17 Input voltage
17.1 Rated noise voltage
17.2 Short-term maximum input voltage
17.3 Long-term maximum input voltage
17.4 Rated sinusoidal voltage
18 Input electrical power
18.1 Rated noise power - characteristic to be specified
18.2 Short-term maximum power - characteristic to
be specified
18.3 Long-term maximum power - characteristic to be specified
18.4 Rated sinusoidal power - characteristic to be specified
19 Frequency characteristics
19.1 Rated frequency range - characteristic to be specified
19.2 Resonance frequency
19.3 Tuning frequency of a bass reflex or passive radiator
loudspeaker system - characteristic to be specified
20 Sound pressure under free-field and half-space free-field
conditions
20.1 Sound pressure in a stated frequency band
20.2 Sound pressure level in a stated frequency
band - characteristic to be specified
20.3 Characteristic sensitivity in a stated frequency band
20.4 Characteristic sensitivity level in a stated frequency
band - characteristic to be specified
20.5 Mean sound pressure in a stated frequency band
20.6 Mean sound pressure level in a stated frequency band -
characteristic to be specified
21 Response under free-field and half-space free-field conditions
21.1 Frequency response
21.2 Effective frequency range
21.3 Transfer function
22 Output power (acoustic power)
22.1 Acoustic power in a frequency band
22.2 Mean acoustic power in a frequency band
22.3 Efficiency in a frequency band
22.4 Mean efficiency in a frequency band
23 Directional characteristics
23.1 Directional response pattern
23.2 Radiation angle
23.3 Directivity index
23.4 Coverage angle or angles
24 Amplitude non-linearity
24.1 Total harmonic distortion
24.2 Harmonic distortion of the nth order (where n=2 or n=3)
24.3 Characteristic harmonic distortion
24.4 Modulation distortion of the nth order
(where n=2 or n=3)
24.5 Characteristic modulation distortion of nth order
(where n=2 or n=3)
24.6 Difference frequency distortion (of the second
order only)
25 Rated ambient conditions
25.1 Temperature ranges
25.2 Humidity ranges
26 Stray magnetic fields
26.1 Static components
26.2 Dynamic components
27 Physical characteristics
27.1 Dimensions
27.2 Mass
27.3 Cable assemblies
28 Design data
29 Indication of the characteristics to be specified
Annex A (informative) Standard measuring enclosure type A
Annex B (informative) Standard measuring enclosure type B
Annex C (informative) Definitions of terms used in Clause 13
Annex ZA (normative) Normative references to international
publications with their corresponding
European publications
Bibliography