Helu
Is it right to claim that multiplying an arbitrary sound with another arbitrary sound in time domain is ring modulation, while multiplying an arbitrary sound with a sine wave is amplitude modulation ?
Thanks!
amplitude versus ring modulation
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- KVRist
- 183 posts since 29 Aug, 2007
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- Skunk Mod
- 21249 posts since 10 Jun, 2004 from Pony Pasture
It's a matter of quadrants.
http://en.wikipedia.org/wiki/Ring_modulation
http://en.wikipedia.org/wiki/Amplitude_modulation <-- with fun animation
Short précis, courtesy of Doepfer:
http://en.wikipedia.org/wiki/Ring_modulation
http://en.wikipedia.org/wiki/Amplitude_modulation <-- with fun animation
Short précis, courtesy of Doepfer:
[edit] What a VCA does is AM.A ring modulator outputs the product (Multiplication X • Y) of the signals at inputs X and Y. It's similar to a VCA, but whereas a VCA only responds to positive voltages at the inputs (2-quadrant multiplication), the ring modulator responds to both positive and negative voltages (4-quadrant multiplication).
The ring modulator thus provides a refinement of amplitude modulation (AM). Ordinary amplitude modulation will output the original carrier frequency fC as well as the two side bands (fC - fM, fC + fM) for each of the spectral components of the carrier and modulation signals - but ring modulation cancels out the carrier frequencies, and just lets the side-bands pass to the output.