Larson Davis 824 - Page 560

C-14 824 Reference Manual 9/29/09
NOTE: A-weighting, C-weighting, and
Flat are measured to ANSI S1.4 and IEC
60651 standards for SLM linearity. 1/3
octave filters listed are measured to the
IEC 61260 standard for Class 0 linearity
which is ±0.3 dB. The numbers in the
table represent SPL levels with a typical
377B41 microphone which has 44.1 mV/
Pa sensitivity.
*NF is electrical noise floor.
Measurement Range (SSA mode only)
0dB Gain 10dB Gain 20db Gain 30dB Gain 40dB Gain 50dB Gain
NF Start End
Rang
e
NF Start End
Rang
e
NF Start End
Rang
e
NF Start End
Rang
e
NF Start End
Rang
e
NF Start End
Rang
e
AW 33 48 128 80 24 38 118 80 15 28 108 80 8 23 98 75 7 20 88 68 6 20 78 58
CW 32 48 128 80 23 38 118 80 16 28 108 80 9 23 98 75 8 20 88 68 8 20 78 58
FLA 32 48 128 80 25 38 118 80 21 33 108 75 21 33 98 65 26 33 88 50 23 40 78 38
16.0 2451288323511883125108832259873-12888601237855
31.5 3431288513511883123108852259873-4228866-4237855
63.0 4401288803311885123108850229876-7158873-7187860
125 2 40 128 88 -2 27 118 91 -3 28 108 80 -2 18 98 80 -9 11 88 77 -8 8 78 70
250 3 37 128 91 -3 25 118 93 -3 15 108 93 -4 15 98 83 -10 8 88 80 -9 8 78 70
500 12 33 128 95 4 25 118 93 -3 15 108 93 -4 13 98 85 -10 6 88 82 -10 8 78 70
1000 10 32 128 96 2 20 118 98 -4 15 108 93 -5 13 98 85 -10 6 88 82 -10 8 78 70
2000 15 32 128 96 6 20 118 98 -2 15 108 93 -5 13 98 85 -8 8 88 80 -8 8 78 70
4000 14 32 128 96 7 20 118 98 0 15 108 93 -2 13 98 85 -6 8 88 78 -6 8 78 70
8000 14 32 128 96 7 20 118 98 1 15 108 93 -1 13 98 85 -2 12 88 76 -3 13 78 65
AUD Mode Specifications
AC/DC output: For AUD, AC and DC
outputs are undefined.
Pulse mode: The pulse test output is
computed from a
Discrete Hilbert
Transform which is
sampled every ½
millisecond. The
Discrete Hilbert
Transform produces a
mathematically correct
sample of the input
waveform envelope.
Time resolution: 0.5 ms to 1.0 seconds
in 0.5 ms increments
Time accuracy: ±1.0 ms
Hilbert transform
magnitude error:
< 0.1 dB
Dynamic range: > 80 dB
Hilbert transform
Sample rate:
2000 Hz