[LAD] Determining Phase

[gene heskett]

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 at boosthardware.com 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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