[PD] downsampling with [block~] causing artifacts

[Martin Peach]

You have a waveform with lots of little square steps in it. Those steps
contain high frequencies in the same way a square wave does. Dynamic range
is determined by the number of bits used to encode the signal, and the
signal/noise ratio, not the sample rate.

Martin

On Fri, May 15, 2015 at 1:18 PM, Alexandre Torres Porres <porres at gmail.com>
wrote:

> Howdy, I have a patch attached to show how downsampling produces
> artifacts/distortion for a 440 sine wave. I don't hear "aliasing" and I
> think it couldn't be foldover at all because 440 is below the nyquist.
> Moreover, I hear harmonic higher pitches - so it seems like a harmonic
> distortion from the original sine wave that I can also still perceive. This
> kind of distortion happens when you have a reduced dynamic range.
>
> Another things is that I heard someone saying how increasing sample rate
> improves dynamic range, but I can't find this information around. Not sure
> it it's really true, if someone says it is so, please send me a source, ok?
> But the thing is that the artifacts from this patch could be the result of
> a smaller SNR.
>
> Hope you can help me sort this out.
>
> thanks
>
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