Larson Davis 824 User Manual

9/29/09 F-5
A-Weighted Sound Levels at
Upper and Lower Limits of the
Linear Operating Range
The following table presents the nominal A-weighted sound
levels at the upper and lower limits of the linear operating
ranges for each level range. The starting point for testing the
level linear errors of the reference range is 114 dB.
Electrical Signal Input Device: The electrical design of the input device to insert electrical
signals into the preamplifier is a series 18pF ± 5% capacitor.
The Larson Davis ADP005 is used for this purpose. The
ADP005 can be used for noise floor testing by attaching the
included short on the front of the ADP005.
Inherent Noise: The inherent Noise on the low range in ISM mode or 50 dB
gain in SSA mode:
31.5 Hz 1 kHz 4 kHz 8 kHz 12.5 kHz
SLM (ISM)
Normal
Range
63 dB to 128 dB 19 dB to 128 dB 18 dB to 128 dB 21 dB to 128 dB 26 dB to 128 dB
Low Range
59 dB to 108 dB 18 dB to 108 dB 18 dB to 108 dB 19 dB to 108 dB 22 dB to 108 dB
SLM&RTA
(SSA)
0 dB Gain
83 dB to 128 dB 43 dB to 128 dB 43 dB to 128 dB 47 dB to 128 dB 49 dB to 128 dB
10 dB Gain
73 dB to 118 dB 33 dB to 118 dB 32 dB to 118 dB 35 dB to 118 dB 39 dB to 118 dB
20 dB Gain
64 dB to 108 dB 24 dB to 108 dB 23 dB to 108 dB 25 dB to 108 dB 29 dB to 108 dB
30 dB Gain
58 dB to 98 dB 19 dB to 98 dB 18 dB to 98 dB 20 dB to 98 dB 23 dB to 98 dB
40 dB Gain
58 dB to 88 dB 18 dB to 88 dB 17 dB to 88 dB 19 dB to 88 dB 22 dB to 88 dB
50 dB Gain
58 dB to 76 dB 18 dB to 78 dB 17 dB to 78 dB 19 dB to 78 dB 22 dB to 78 dB
Frequency Weighting Total Noise
1
Electrical Noise
2
A16 7
C1913
Flat 24 21

Larson Davis 824 Specifications

General

Brand	Larson Davis
Model	824
Category	Measuring Instruments
Language	English