AS3460
ALC Tuning Guide
Demo Kit Manual
• PUBLIC
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• v3-00 • 2021-Nov-08
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7.10.1
Algorithm Management
The algorithm calculates an estimate of the noise cancellation effectiveness. If the noise cancellation
is effective, the algorithm knows that its current leakage estimate is close to the real leakage and it is
therefore safe to activate feedback ANC. If your headphone does not provide a good noise
cancellation, you might need to increase these thresholds. Disable feedback ANC, and at different
leakages, monitor the noise cancellation attenuation and note at which value it stabilizes. Set the
noise cancellation effectiveness threshold 1 75% of this value. Threshold 2 should be around 150% to
200% of threshold 1.
Figure 102:
Algorithm Management Window
The algorithm's estimate of the current leakage condition is based either on the ratio of the adapted
feed forward gains or on the observed driver response. Which method is used depends on the music
to noise ratio. The thresholds at which the algorithm switches to the different methods are configured
using the music impact thresholds. Below the first threshold, it is assumed that there is no music and
