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2
TECHNICAL DESCRIPTION
The DPA High-Voltage microphones types: 4003, 4004, 4012, 4016,
4041-S, and 4041-T are powered via the Two-Channel High-Voltage
Microphone Amplifier HMA5000, which supplies 130 V to their built-in
preamplifiers giving the microphones excellent SPL handling capabili-
ty. But the HMA5000 is not only a power supply unit, it is also a micro-
phone amplifier with outstanding specifications.
The Microphone Amplifier
The HMA5000 uses state-of-the-art, low-noise operational amplifiers
from Analog Devices‚ in the input stages. Each channel input features
independently switchable gain by +30 dB, +20 dB, +10 dB, 0 dB, -10 dB
or -20 dB corresponding to a maximum input voltage of 0.5 -160 V
peak.
The signal path in the HMA5000 is completely transformerless, which
gives the microphone amplifier an excellent frequency range from 10
Hz to 100 kHz (-1 dB). The HMA5000 has a Crosstalk attenuation better
than 90 dB measured with any gain setting.
Featuring both electronically balanced and single ended line-level out-
puts, the HMA5000’s impedance converters can drive up to 300 m
(984 ft) of microphone cable. Both input channels are single ended
and it is required to use the dedicated DPA Microphone cables in order
to optimize noise rejection.
Polarity Switch
A polarity switch for each channel is found on the rear next to the
output connector of the corresponding line output.
In the position "0°" the HMA5000 system has absolute phase from
input to output.
Switching to "Inv." (Inverse) will invert the phase.
(See Fig. 1 and Fig. 2 for pin designation of the output and input con-
nectors).
Polarity
DPA 4003
positive going
positive going
negative going
DPA 4004
positive going
positive going
negative going
DPA 4012
positive going
positive going
negative going
DPA 4016
positive going
positive going
negative going
DPA 4041-S
negative going
negative going
positive going
DPA 4041-T
negative going
negative going
positive going
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2
3
Fig. 1. External view of the output connector of the HMA5000.
Positive going
sound pressure on
microhone type:
- produces this elec-
trical signal on the
HMA5000 input
pin 4:
When switch in 0
°
-
position then
HMA5000 output
on pin 2 is:
When switch in
"Inv."-position,
HMA5000
output on pin 2 is:
MANUAL DPIHMA5000 26/08/04 11:12 Side 2
