Note:
The audio signal lasts two seconds. For better clarity only a part of 0.5 seconds
is shown.
The sine oscillation looks unregular for some frequencies erroneously, because only
shown a selection of certain values is presented for reasons of speed.
By moving the appropriate controllers (red) the frequencies, that shall be filtered, (horizontal controllers: bass and treble filter) as well as the intensity of filtration (vertical controller) can be varied.
The aim should be to remove the noise so the starting signal is reconstructed as well as possible.