Additive Synthesis is the foundation of modern sound design.
Additive synthesis works by composing sound through the combination of sine (or other) sound waves & files.
Through this technique you can technically generate literally any sound imaginable,
and even the vocoded human voice.
Essentially, it works by analyzing the waveforms of any given sound file & using a Fourier Transform
to plot an incoming linear signal into an oscillator graph composed of thousands of sine waves, in turn approximating the original source to a high degree of accuracy.
In the use of practical music production, we can use this technique to create our own synth patches that
use a combination of different sine waves; for example, layer a synthesized white noise underneath a tambourine,
or a kick drum to create a more textured sound, as noted below;