Modulation

Disciplines of Study [DoS]  >  Acoustics  ]

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

Bateman, Wayne (1980). Introduction to Computer Music
BERMÚDEZ COSTA, Juan (1977). Nueva Generación de Instrumentos Musicales Electrónicos (The new generation of electronic music instruments)
Chadabe, Joel (1975). The Voltage-Controlled Synthesizer
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.
NUÑEZ, Adolfo (1993). Informática y Electrónica Musical - 2da. edición, revisada (Musical Electronics and Informatics - 2nd edition, revised)
Pottier, Laurent (2003). {Straps} : pièce d’Eryck Abecassis pour ensemble et électronique en concert
Risset, Jean-Claude (1996b). Real-World Sounds and Simulacra in my Computer Music
Risset, Jean-Claude (2005a). Sur l’impact de l’œuvre scientifique, technique et musicale de John Chowning

Top

order lasuna femara manufacturer order zocor buy modalert online india diflucan 200mg a-ret lowest price in mayami azithromycin pharmacy information caverta usa information about generic olanzapine premarin without a presciption in mayami http://onpes.gouv.fr/?gav=983515 naltrexone cheapest lipitor prices in india amlodipine 0.625 mg capsule nexium 500 mg buy waklert uk in new york bactrim pill http://tg.auf.org/?har=156212 http://razon.com.mx/?dfa=20773 azithromycin without http://sfc-classification.net/?hty=337155 info about prices prilosec generic modafinil provigil modalert buy oleanz diflucan tablets price of nexium 30 1 g azithromycin zithromax in mayami http://tg.auf.org/?har=467248 piracetam hong kong in united states http://penclub.fr/?hah=8898 cilostazol 50mg tablets bimatoprost discount orlistat pills orlistat pill bupropion er 12 hr in india orlistat pill generic bupropion pricing for bimatoprost ophthalmic solution 0.03 premarin over the counter olanzapine generic in uk enalapril 2.5 mg b i d cost for 10mg lipitor diflucan 60 mg cheap zocor in new york ciprofloxacin no prescription in uk buy kamagra about lipitor prices simvastatin prescription on line price of orlistat more info about bactrim ds 800 160 tabs discount diflucan price of bupropion xl generic nexium without prescription