User manual

Audio Analyzer
4-68
AM700 Audio Measurement Set User Manual
A flat settling curve applies the Tolerance and Resolution parameters backwards
horizontally instead of exponentially and will yield the most accurate settled data
points but at the expense of increased settling time.
Level Min. You can specify level minimum value. Level values below the specified
minimum are not plotted.
Delay Time. In Regulation mode and in closed-loop XY mode, the Audio Analyzer
restarts the settled data point process each time the generator frequency or
amplitude is changed. This causes the Audio Analyzer to pause the delay amount of
time before looking for the first data point (see Figure 4-29). By adjusting the delay
you can allow for the response time of the audio generator and the propagation
delay time of the device under test. A minimum of 1.0 second delay is suggested for
Regulation mode measurements; smaller delays can be used in closed-loop XY
mode, but the delay time can require adjustment to obtain a useful measurement.
Data below minimum level
is not considered
L1
L2
Level Min
Dwell
Delay from generator step to
begin looking for new data
Generator steps
Figure 4-29: Regulation mode delay time setting
For example, assume that because of audio generator response time and propagation
time in the device under test, 0.7 sec is required after adjusting the audio generator
before attempting to acquire a response from the device under test. If the delay is set
to some smaller value, the generator is adjusted and the analyzer attempts to acquire
a response before the new settings arrive at the input of the AM700. The resulting
incorrect data can cause duplicate data points to be plotted on the display.