A command to filter every selected Sound object. The resulting Sound object has a lower spectral slope.

The reverse of Sound: Filter (pre-emphasis).... For an example, see Source-filter synthesis.

Setting

From frequency (Hz)

the frequency F above which the spectral slope will decrease by 6 dB/octave.

Algorithm

The de-emphasis factor α is computed as

where Δt is the sampling period of the sound. The new sound y is then computed recursively as:

Links to this page

• Filtering
• Sound: De-emphasize (in-place)...