Here, a sine function is replaced with samples at 32 points. Unlike quantization, the function can take any value at those points; but the function is flat between these samples. 32 points per cycle corresponds to a sampling frequency of 220 × 32 = 7040 Hz (at the default playing frequency of 220 Hz). This causes aliasing, where new, unwanted frequencies will be introduced. For example a frequency of 220 Hz, when resampled, will have aliases at 6820 Hz (7040-220), 7260 Hz (7040+220), 13860 Hz (7040*2-220), and so on. These frequencies can be heard when the function is played (by clicking the Sound checkbox).

Press Sine to get a clean sine wave, and play it for comparison. Press Resample to resample it, multiple times to use a lower sampling rate.

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Generated Wed May 17 2017