Common Types of Audio Synthesis
Subtractive Synthesis: The basis of subtractive synthesis is that an incoming audio signal is then attenuated by a filter to alter the timbre of the output signal. This method is widely used among synthesizers, and can be used in conjunction with other audio synthesis methods.
Additive Synthesis: A method of audio synthesis that generates a timbre by adding multiple sine waves together. Overtones produced by a musical instrument are sine waves of different frequencies and amplitudes.
Frequency Modulation Synthesis: FM synthesis is based upon changing the timbre of a simple oscillating tone (such as a square wave or sawtooth wave) by modulating the wave's frequency with another frequency that is within the audible spectrum. This often leads to distorted, dark gritty timbres.
Sample-Based Synthesis: Waveforms are not generated using this method. They are instead sampled sounds of other instruments, or other waveforms. The pitch of the sample is them modulated according to the key pressed on the synthesizer. Adjusting the pitch of a sample to the extreme lows can often produce undesired results, as the original sample has been stretched too much. This can lead to audible stepping if proper smoothing techniques are not applied.
Granular Synthesis: Similar to sample-based synthesis in that the fundamental sound is produced by a sampled sound, but granular synthesis is based on millisecond sound samples. A conventional sampled sound can be split into hundreds of smaller samples, called grains. These grains can then be played at random, and can be played at different speeds, volumes, phases, frequencies, and other parameters.
Wavetable Synthesis: A method of audio synthesis that generates sounds from digital signals. Wave table synthesis stores digital samples of sound from various instruments, which can then be combined, edited, and enhanced to reproduce sound defined by a digital input signal.
Additive Synthesis: A method of audio synthesis that generates a timbre by adding multiple sine waves together. Overtones produced by a musical instrument are sine waves of different frequencies and amplitudes.
Frequency Modulation Synthesis: FM synthesis is based upon changing the timbre of a simple oscillating tone (such as a square wave or sawtooth wave) by modulating the wave's frequency with another frequency that is within the audible spectrum. This often leads to distorted, dark gritty timbres.
Sample-Based Synthesis: Waveforms are not generated using this method. They are instead sampled sounds of other instruments, or other waveforms. The pitch of the sample is them modulated according to the key pressed on the synthesizer. Adjusting the pitch of a sample to the extreme lows can often produce undesired results, as the original sample has been stretched too much. This can lead to audible stepping if proper smoothing techniques are not applied.
Granular Synthesis: Similar to sample-based synthesis in that the fundamental sound is produced by a sampled sound, but granular synthesis is based on millisecond sound samples. A conventional sampled sound can be split into hundreds of smaller samples, called grains. These grains can then be played at random, and can be played at different speeds, volumes, phases, frequencies, and other parameters.
Wavetable Synthesis: A method of audio synthesis that generates sounds from digital signals. Wave table synthesis stores digital samples of sound from various instruments, which can then be combined, edited, and enhanced to reproduce sound defined by a digital input signal.