Resonator

A resonator allows a very narrow range of frequencies to survive, and filters out the rest. Filters are used to shape noise or other sounds, so that they become louder at some frequencies and softer at others. In this example it sounds a bit like blowing over the top of a glass bottle.

The resonator here is an implementation of the ‘resonz’ filter, which is an example of a constant gain band pass filter, as described here.

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