Preamplifiers for Sound Level Meters

Preamplifiers for Models 721, 821, 831, 831C and LxT

Larson Davis offers a number of microphone preamplifiers for a variety of applications. Ruggedly built, they can drive lines up to 500 feet.

 PRM821PRM721PRM831 PRMLxT1 PRMLxT1L
Diameter (inch) 0.50.50.5 0.5 0.5
Connector 5-pin
Switchcraft®
5-pin
Switchcraft®
5-pin
Switchcraft®
5-pin
Switchcraft®
5-pin
Switchcraft®
200 V Polarization NoNoNo No No
Voltage (min) 15 VDC15 VDC15 VDC6 VDC 6 VDC
Voltage (max) 36 VDC36 VDC36 VDC 15 VDC 15 VDC
Frequency 5 Hz to 126 kHz5 Hz to 126 kHz5 Hz to 126 kHz 4 Hz to 40 kHz 4 Hz to 40 kHz
Attenuation (typical) 0.8 dB0.8 dB0.08 dB 22.8 dB 1.2 dB
Noise
(typ A-weighted)
2.3 µV2.3 µV-1.6 µV -1.1 µV -1.8 µV
Input Impedance 10 GΩ10 GΩ10 GΩ 10 GΩ 10 GΩ
TEDS NoNoNo No No