Inverse Fourier transformations obtain chronological sequences of amplitudes from given energies at known frequencies.

Shape the sound by its frequency spectrum and shift it to higher and lower ranges of frequency or modify the spread of controlled points along the frequency spectrum.

The upper row of pixels in the array plot at the top visualizes the signs of the real parts for the shifted input spectrum. The lower row of pixels represents the signs of their imaginary parts.

The frequencies of the sixteen modes currently under slider control are given between the upper and lower sliders which specify real and imaginary power at those frequencies. Click their buttons to reset their values to 0. Click again to reset to random values. Current real and imaginary modes are given as tooltips.

The selected representation at the bottom visualizes the amplitudes obtained from the inverse Fourier transform. Select the sound representation to obtain the standard spectrum amplitude plot and play it by clicking its tiny play button.