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



English - Español - Français - Deutch - Italiano

Alphabetical order - Chronological order

Top more gefitinib tabs buy fluticasone inhaler buy dapoxetine 60mg order azithromycin online in mayami allium sativum candida information bupropion hcl 100mg cheap generic caverta buy generic oracea tenofovir viread orlistat online in india nuvigil generic buy letrozole and nolvadex buy cernos gel online stendra memantine usa manufacturer gleevec cost at caremar bupropion hlc sustanon 250 pills bupropion hcl sr 150mg tab bupropion er 150 cost bupropion 150 mg er femara without a perscription or membership in mexico information buy finasteride over the counter bupropion prices imatinib approval buy femara in canada viread buy viread tenofovir bupropion er tab 300 mg kamagra oral jelly buy fluticasone propionate nasal spray 50mcg info about imatinib prescription otc bupropion hcl sr orlistat no prescription buy memantine online canada in mayami vasotec enalapril low cost piracetam sildenafil citrate 100mg oral jelly uk bactrim 800 160 generic discount in france buy modalert no prescription fluticasone prop in usa buy generic namenda in mexico azithromycin overnight mail bupropion tab orlistat of ranbaxy india ciprofloxacin hcl 500 mg about teva budeprion xl buy bactrim ds without a presciption garlic himalaya product more info about eriacta ranbaxy more info buy kamagra oral jelly paypal ginkgo arcalion 200