Crest Audio LH2 LOUDSPEAKER, Технические характеристики, Страница: 2 / 4

Specifications
LH TM 2 Loudspeaker
Power Handling
Crest Audio rates this unit’s system power
handling using a modified form of the AES
Standard 2-1984. Utilizing audio band lim-
ited (20 Hz - 20 kHz) pink noise with
peaks over four times the RMS level, this
strenuous test signal assures the user that
every portion of this system can withstand
high inpact music. The test signal contains
large amounts of low frequency energy,
effectively simulating the frequency con-
tent of live music situations. High frequen-
cy test signals expose the speaker system
to synthesized tones that may extend
beyond audiobility. This rating is contin-
gent on having a minimum of 3 dB of
amplifier headroom available so as to
ensure that clipping does not occur.
Frequency Response
This measurement is useful in determin-
ing how accurately a given unit repro-
duces an input signal. The frequency
response of the LH
TM 2 (Figure 1) is meas-
ured at a distance of 1 meter using a 1
Watt (into the nominal impedance) swept-
sine input signal.
Directivity
Beamwidth is derived from the -6 dB
points from the polar plots which are
measured in a whole space anechoic
environment. Q and Directivity Index
(Figures 3 & 4) are plotted for the on-axis
measurement position. These are specifi-
cations that provide a reference to the
coverage characteristics of the unit. These
parameters provide insight for proper
placement and installation in the chosen
environment.
20 50 100 200 500 1k 2k 5k 10k 20k
Frequency (Hz)
1
10
100
Q & Directivity Index
Q
Figure 4
20
10
Di
0
20 50 100 200 500 1k 2k 5k 10k 20k
Frequency (Hz)
30
40
60
80
100
140
180
300
360
Beamwidth
(Degrees)
Beamwidth
Vertical
Horizontal
Figure 3
20 50 100 200 500 1k 2k 5k 10k 20k
Frequency (Hz)
1
2
3
5
10
20
30
50
100
Impedance
Z
( )
Figure 2
Lower Curve: Midrange Contour = High, Upper Curve: Midrange Contour = Norm
20 50 100 200 500 1k 2k 5k 10k 20k
Frequency (Hz)
70
80
90
100
110
dB
SPL
(re
20
Pa)
Amplitude Response (1W 1m On-Axis)
Figure 1
Lower Curve: Midrange Contour = Norm, Upper Curve: Midrange Contour = High