[PD] Combat aliasing!

Matteo Sisti Sette matteosistisette at gmail.com
Thu Apr 1 13:10:21 CEST 2010

Pierre Massat escribió:
> Wait, so aliasing occurs when the signal is sampled?
> So if i have this patch :
> [adc~]
> |
> |
> |
> [dac~]
> and if the signal already contains frequencies above the Nyquist, i will 
> get aliasing? 

Well obviously (or not) a real-world ADC (e.g. a sound card) always 
includes an analog lowpass filter that cuts off the frequencies above 
Nyquit before actually digitalizing!!!!

However, when you sample a mathematically generated signal, such as:

[phasor~ 1000]

then no filtering occurs, and aliasing does occur.

More evident:

[osc~ 40000]

Matteo Sisti Sette
matteosistisette at gmail.com

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