User talk:PeterSampson/Sand-Box

Artifacts

You may get tinkly artifacts when individual pure tones in the audio are near the threshold to be preserved - they are small pieces of the background soundscape that survived the thresholding, perhaps because the background noise is slightly different from the fingerprint or because the main sound has overtones that are imperceptible but that boost them slightly over the threshold.

The Sensitivity slider biases the thresholds of all frequency bands. Higher settings will thus reduce the number of artifacts, but at the risk of introducing the opposite discrimination error, in which parts of the desired signal are misclassified as noise and so reduced. The purpose of the Residue radio button is to pass the difference between the original sound and what would result from choosing Reduce. When the Sensitivity is excessive, "tinkly-bells" artifacts will be heard in Residue rather than in Reduce, and where the original had louder sounds, rather than in the pauses between sounds. By previewing the results of Residue before applying the effect, the best Sensitivity balance can be found.

The Frequency Smoothing slider does not affect the number of artifacts, but it can make each less evident by spreading the effects of discrimination errors among nearby frequency bands.