[PD] Normaliizing sinus mix

William Brent william.brent at gmail.com
Mon Apr 30 15:55:05 CEST 2018


Maybe I'm misunderstanding what you're asking, but if the waveform is
visually outside of the +1/-1 table bounds, the peak amplitude has to be
greater than 1.0 too. Peak amplitude is the maximum of the absolute value
of a waveform...max(abs(x)). When I run

sinesum 512 1 0.5 0.25;

I get a peak amplitude of 1.38751. Dividing all samples in the table by
that value makes the new peak 1.0, and all other values scaled
proportionally. So if you want to normalize without using the built-in
"normalize" function, you can safely do it this way.

On Mon, Apr 30, 2018 at 4:25 AM, João Pais <jmmmpais at gmail.com> wrote:

> Hi William,
>
>
> Hi Joao, you need to find the peak amplitude, max(abs(x)), and divide all
> samples by that.
>
>
> I'm not sure: if I use the amplitudes 1 0.5 0.25, the peak amplitude is 1,
> and the wave is clearly outside of the 1/-1 boundaries.
>
> Basically what I'm trying to do is to find out what is the formula that
> does the "normalize" function.
>
> Best,
>
> Joao
>
> On Apr 29, 2018 7:55 PM, "João Pais" <jmmmpais at gmail.com> wrote:
>
> Hello list,
>
> I was curious about the following math issue: when defining a waveform
> using "sinesum 0.8 0.2 0.1", what would be the formula to normalize the
> wave to 1?
> I tried adding all the values (=1.1 in this case), getting the inverse
> value and multiplying the list with that. Although the sum of the values
> is 1, the resulting wave isn't normalized to 1 the same way the
> "normalize
> 1" command would do it. So I imagine some higher math is required?
>
> Also, is the process the same if the wave components are harmonic or not
> (that is, multiples of the base frequency)?
>
> Best,
>
> jmmmp
>
>


-- 
William Brent
www.williambrent.com

“Great minds flock together”
Conflations: conversational idiom for the 21st century

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