Additive Synthesis

From MadTracker Wiki

Additive Synthesis is an audio-synthesis process that generates sound by combining multiple simple sine waveforms, and then processes them further with envelopes. This allows it to emulate the timbre of actual musical instruments. Additive Synthesis achieved with multiple sine oscillators, tuned to multiples ( or ratio's ) of the base frequency. These oscillators often have their own volume envelopes as well, which allows the final product to sound very real and dynamic.

An instrument's timbre is made up of multiple different harmonics that change over time. Additive synthesis simulates this by generating a number of waveforms that are tuned to different harmonic frequencies, each with its own amplitude and envelope.

Most additive synths have an noise oscillator on board to add just that finishing touch to a re-synthesis, for example if you emulate a flute you want to hear just that bit of hiss when the player blows thru the mouthpiece.