9/29/09 AUD (Optional) 13-1
CHAPTER
13
AUD (Optional)
The System 824 precision sound level meter with the 824-
AUD firmware option is the heart of the Larson-Davis audi-
ometer calibration system. This instrument and its firmware
maintain and exceed the performance of previous Model
800B-based systems when used with the AUDitâ„¢ software.
However, the System 824 with 824-AUD firmware alone
still possesses numerous analysis features useful for audiom-
eter testing tasks such as:
• Level
• Frequency
• Linearity
• Total harmonic distortion
• Pulse measurements
• Crosstalk
• Frequency modulation
• Narrow band, broad band and speech noise
Some of these tests are slightly more tedious when
performed manually. The following overview of the 824-
AUD instrument should be augmented by familiarizing
yourself with the 824 Reference Manual.