[sdiy] Harmonic bandwidth

[Jim Palmer]

interestingly moving my head between the two sounds (fading in and out)
has a much more dramatic effect than moving it during the sound.
this is my magnificent brain correcting for the motion, no doubt...

limiting the test to 2 harmonics suggested another test to isolate the speaker.
i gots 2 speakers, so i isolate the two harmonics and let them mix
in the air instead of in the speaker.  this results in indistinguishable
clips.

so barring similar tests with more harmonics (thus more speakers) i
am ready to conclude that the audible difference is due to speaker
nonlinearity.

but does this mean we can disregard it?  we are electronic musicians no?
always we rely on speakers (often far from ideal ones) to create
our sounds.  i think that we can no longer disregard phase differences
and phase distortions in our analysis.  what a can of worms this
opens up.  (if only having to admit some of the audiophile voodoo may be true)

Ian Fritz wrote:
> At 10:45 AM 1/9/2008, Jim Palmer wrote:
> 
>> is it possible to get frequency distortion in a speaker??
>> i'm hearing this one as a tiny pitch change
> 
> There *can* be frequency distortion from the Doppler effect -- a low 
> frequency signal can modulate the pitch of a higher frequency one.  I 
> have no idea whether this could be playing a role.  And as pointed out 
> before, a speaker could be asymmetric in its response.  But I think you 
> should try moving your head around while playing one of your waveforms 
> back and see if the changes in timbre are similar to what you get when 
> you switch waveforms.  Also  -- from psychoacoustics we know that small 
> pitch changes and small timbre changes can be confused.
> 
> Interesting stuff!
> 
> Ian
> 
>