Intermodulation Distortion Settings - Interacoustics Affinity 2.0 Additional Information

2.0
Affinity Additional Information
3.8.2.5

Intermodulation Distortion Settings

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1) Ensure that Intermodulation Distortion is marked in the left hand side of the screen. The name of
the test will then appear in the Name of selected test section. Note the option to write a new name
for the test in this section (e.g. "Intermodulation Distortion 500, 1000 & 2000 Hz").
2) Frequency Selection:

Frequencies: Select the frequencies to be included in the Intermodulation Distortion
measure by ticking the boxes.
3) Settings:

Input level: Select the input level (expressed in dB SPL) using the slider.

Difference F2-F1: Decide the difference between the first two formants (expressed in Hz)
using the slider. When the two frequencies are close to each other a coupling (third signal)
between them will be greater than if the distance was larger.
4) Tolorance Limits:
 Set limits: Press the button to define individually preferred tolerance limit values. By applying
tolerance limits to the recording, it will be possible to easily document whether a curve is
inside tolerances or not. In the tolerance limits screen the upper limits may be entered as
numerical frequency specific values.
Note, however, that this is only possible for the frequencies chosen in the Frequency
selection see point 2) above. Alternatively, limits may be entered by clicking with the mouse
directly on the dots in the co-ordinate system and dragging them to the preferred position

Display Tolerance Limits: Tick the box to activate the tolerances which will then be shown
on the graph in the front screen.
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