Re: [LAD] Determining Phase

On Sunday, June 26, 2011 02:48:01 PM Gordon JC Pearce did opine:

> On Sat, 25 Jun 2011 16:23:29 +0200 (CEST)
>
> pshirkey@email-addr-hidden wrote:
> > Hi,
> >
> > Can anyone point me to a simple code example for how to determine the
> > phase at a specific time in a waveform?
> >
> > ex. if I have a sample that is 5 seconds long and want to know the
> > phase at 2.5 seconds
> >
> > I'm open to code in any language or a scripted example if such a tool
> > exists. If there is an ui which has that feature I am also interested.
>
> There isn't really a way to do this. How would you tell the difference
> between 0.5*sin(pi/2) and 1.0*sin(pi/6) - try it and see, what are the
> answers?
>
> If you want to determine phase you need to know the amplitude. The only
> sane way to do both is to use a complex sample with an in-phase and a
> quadrature component.
>
> Gordon MM0YEQ

I do not see how a repeatable, and therefore measurable quadrature
component can be developed in a complex, multi-frequency waveform since the
quadrature component is just as frequency dependent as any other method of
measurement.

Since the human ear is not sensitive to phasing, other than diffs between
the two ears from delay/echo/reverb effects that help us determine
direction of src, to me, this argument is moot and possibly a waste of
time.

Cheers, gene

-- 
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