Modulation

Sound Production and Manipulation [SPM]  >  Sound Shaping  ]

The process by which one signal is used to modify another. The controlled signal is referred to as the ’carrier’, and the controlling signal as the ’modulator’. It is of the greatest importance in both sound synthesis and signal processing.

The two main parameters of a sound to which modulation is commonly applied are those of amplitude (loudness) and frequency. Amplitude modulation of a signal causes changes in loudness in that signal. If the control signal is a slow regular waveform (e.g. a sine wave) the result is a tremolo - similar to (and often confused with) vibrato, except that there is no pitch deviation. Once the frequency of the modulator is raised above 10 to 15 Hz the tremolo amalgamates into a complex sound with added frequency components derived from the pitches of carrier and modulator. An irregular or transient control signal is generally associated with envelope generation.

Frequency modulation causes the pitch of the carrier to rise and fall according to the shape of the modulating waveform. If this is, as above, a slow regular waveform, the result is vibrato if the depth of the modulation is low, otherwise becoming a wide siren-like effect. If the modulating waveform is a series of discrete steps, the result is a series of discrete pitches. Particularly complex sounds arise when the frequency of the modulator is close to or even higher than that of the carrier. (Source - Richard Dobson (1992). A Dictionary of Electronic and Computer Music Technology. Oxford University Press.)

Ring modulation allows for the sum and difference of two input frequencies to be combined to create a new sound. Often one of these frequencies is at a sub-audio level allowing the creation of a sound of two similar frequencies, frequently with noisy textural characteristics.

 

See also:

Amplitude, Frequency, Frequency Modulation Synthesis

 

Bibliography:

English - Español - Français - Deutch - Italiano

Alphabetical order - Chronological order

Geslin, Yann (2001). Le studio 123
Lai, Antonio (1999). La fonction compositionnelle des modulateurs en anneau dans {Mantra} (Karlheinz Stockhausen)
Moles, Abraham A. (1957). Machines à musique. L’apport des machines électronique et électroacoustiques à la nouvelle sensibilité musicale.
Pottier, Laurent (2003). {Straps} : pièce d’Eryck Abecassis pour ensemble et électronique en concert
Risset, Jean-Claude (2005a). Sur l’impact de l’œuvre scientifique, technique et musicale de John Chowning

Top

coumadin ancedotes in mexico evista 60mg http://www.redligare.org/spip.php?buy=788039 motrin nosebleeds in india http://www.redligare.org/spip.php?buy=628399 plavix drug programs propecia exam actonel monthly prescription male sex buspar http://www.redligare.org/spip.php?buy=828138 buying nexium online exelon limerick pa seroquel nizoral ftv lasix im arimidex thinning hair http://www.redligare.org/spip.php?buy=873696 januvia similar fmls computer requirements information vancomycin nicu dilution clomid process medicine lamictal amoxicillin liver actos drugs in california athletes on zoloft diflucan duration zyban high als celebrex seroquel withdrawl information about zithromax purchace optifast verses slimfast tripping on benadryl about canary erythromycin toxic liquid amoxicillin vermox new zealand gus savella in mexico http://www.redligare.org/spip.php?buy=463468 melatonin hot flash benefits of celexa lipitor substitute lasix kcl brahmi bacopa http://www.redligare.org/spip.php?buy=300129 belching lexapro in france info about clonidine hlc ponstel advil coumadin caffeine more info about allopurinol thrombocytopenia lexapro in myasthenia after stopping lamictal anup sidhu trileptal cozaar 12.5 lipitor spine herniated valtrex 1000mg in california