AM Synthesis Flashcards
AM Synthesis stands for:
Amplitude Modulation. In this case, we are changing the timbre of the audio waveform by changing the level of volume over time.
What is one basic way that we change amplitude over time?
Every time a note has an envelope that shapes the volume, that is a basic for of AM synthesis.
Both AM and FM synthesis work by utilizing this basic structure:
Modulator-Carrier Format. Modulator is the wave that changes the wave form. Carrier is the waveform that makes the sound.
What are sidebands?
In AM synthesis, sidebands are the sum and difference of the audio frequencies when running at audio rates. For example, If we had a carrier frequency of 500Hz and a modulator frequency of 200Hz, the sidebands produced would be at 300Hz and 700Hz.
What happens to the amplitude of a waveform as it dips down to zero in AM synthesis?
The amplitude of the waveform turns off after it reaches the zero threshold.
What is Ring Modulation?
Ring Modulation (RM) is a form of Amplitude Modulation (AM) in which the amplitude is allowed to dip down to zero, as opposed to other methods of AM which include a DC Offset that acts like a depth or intensity control.
What happens to the waveform after it reaches zero in ring modulation.
The waveform is inverted.
How are sidebands in ring modulation different than the sidebands in AM synthesis?
The sidebands are alone - there is no fundamental frequency in Ring Modulation.
Why is AM Synthesis/Ring Modulation tricky to use?
The carrier will not track pitch unless the modulator and the carrier have a harmonic relationship.
What is another name for slow AM synthesis?
Tremolo
AM synthesis is often useful for producing what type of sounds?
Robot-machine sounds
