Pulsify Effect

## Pulsify Effect v1.0

By Steve Horne, 6 March 1999

This effect provides an easy way to vary the timbre of a note over time. It works by mixing a pulse waveform into the original input.

The pulse wave is derived by spotting zero crossing points in the input, and is scaled according to the recent average amplitude of the input.

The level of the effect can be faded in and out. The fading follows a simple 'decay' curve. That is, when a new target level is set, the level of the effect changes rapidly at first but slows down as it approaches the set value. It never quite reaches the set value (unless the initialise parameter is used). The rate of the fade is set as a half life - the time needed to cover half the distance between the current level and the target. Smaller values give faster fades.

If the 'Level [initialise]' parameter is set, the level of the effect will jump immediately to the set value. Also, the target will remain at that level unless the target is explicitly set - any previous target level is lost.

If you have any comments, please e-mail them to steve@lurking.demon.co.uk.