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Date: 20 Oct 2006 21:35:08
From: Radium
Subject: Increasing the pitch of solar sound without decrease playback time?
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Hi:
Adobe Audition seems to be able to change the pitch of an audio file
without changing the speed at which it plays.
http://www.adobe.com/products/audition/overview2.html#kmhead3
"Time and pitch processing: Change tempo without shifting pitch - or
shift pitch without changing tempo - and never introduce audio
artifacts."
I wonder if this technique could enable astronomers to hear the sun
"sing" with having to increase the speed of the data they record. The
sun's acoustic signals are way too low-pitched for humans to hear. So
either the recording of the sun's acoustic signals has to be sped up
until the pitch is high enough for humans to hear or the pitch itself
needs to be changed using some intense processing [such as that of
Adobe Auditon]. It seems that the former method is used instead of the
latter. Why? If the audio software has sufficient abilities to increase
the pitch of infrasonic signals to that in the human audio-range --
without increase the playback speed -- then why isn't such a method
used?
An advatange I see is that if the infrasound if for 5 minutes,
increasing the pitch won't decrease the amount of time of the
recording.
Of course. An EXTEREMLY high-resolution of pitch-changing would have to
be used in order to ensure that artifacts are not present. Such is not
yet available.
Thanks,
Radium
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Date: 21 Oct 2006 09:17:54
From: rotchm@gmail.com
Subject: Re: Increasing the pitch of solar sound without decrease playback time?
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Oh, and here too....
http://www.exploratorium.edu/exhibits/highest_note/ex.about.fr.html
Quite fun...
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Date: 21 Oct 2006 09:07:15
From: rotchm@gmail.com
Subject: Re: Increasing the pitch of solar sound without decrease playback time?
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wiki roger shepard -shepard tone.
Shepard is like a M.C Escher. Check out shepard's art too on google
images.
His tone thing is inspired by Cantor and Weierstrass functions.
See book: "Fractals, chaos, power laws" by M. Schroeder, p95-98
Have fun.
> > On a similar note ;) there are (audible) sounds such
> > that when played back at twice its speed, we actually hear it at a
> > lower pitch !
> >
>
> Really? I find that amazing, and deeply counter-intuitive. But I realize
> that counter-intuitive isn't enough not to believe you. Could you expand a
> bit please? (meaning "could you please elaborate" - not "could you please
> grow wider"). Or supply an example? I'm fascinated! Are these tones audible
> both when played "naturally" and when pitch-shifted? Does this effect happen
> with natural or is the effect limited to exotic manufactured sounds? Is this
> an artefact of digital sampling?
>
> Al
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Date: 20 Oct 2006 22:23:42
From: rotchm@gmail.com
Subject: Re: Increasing the pitch of solar sound without decrease playback time?
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> Adobe Audition seems to be able to change the pitch of an audio file
> without changing the speed at which it plays.
>
> http://www.adobe.com/products/audition/overview2.html#kmhead3
On a similar note ;) there are (audible) sounds such
that when played back at twice its speed, we actually hear it at a
lower pitch !
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Date: 22 Oct 2006 01:25:18
From: Al
Subject: Re: Increasing the pitch of solar sound without decrease playback time?
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<rotchm@gmail.com > wrote in message
news:1161408222.515575.101490@f16g2000cwb.googlegroups.com...
>> Adobe Audition seems to be able to change the pitch of an audio file
>> without changing the speed at which it plays.
>>
>> http://www.adobe.com/products/audition/overview2.html#kmhead3
>
> On a similar note ;) there are (audible) sounds such
> that when played back at twice its speed, we actually hear it at a
> lower pitch !
>
Really? I find that amazing, and deeply counter-intuitive. But I realize
that counter-intuitive isn't enough not to believe you. Could you expand a
bit please? (meaning "could you please elaborate" - not "could you please
grow wider"). Or supply an example? I'm fascinated! Are these tones audible
both when played "naturally" and when pitch-shifted? Does this effect happen
with natural or is the effect limited to exotic manufactured sounds? Is this
an artefact of digital sampling?
Al
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Date: 21 Oct 2006 18:39:44
From: Radium
Subject: Re: Increasing the pitch of solar sound without decrease playback time?
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Ben Rudiak-Gould wrote:
> Radium wrote:
> > http://www.adobe.com/products/audition/overview2.html#kmhead3
> >
> > "Time and pitch processing: Change tempo without shifting pitch - or
> > shift pitch without changing tempo - and never introduce audio
> > artifacts."
>
> They're exaggerating, as Spock would say. It does introduce artifacts. But
> it works well as long as you don't push it too far.
>
> > I wonder if this technique could enable astronomers to hear the sun
> > "sing" with having to increase the speed of the data they record.
>
> I think that you can generally raise the pitch by around an ave, maybe a
> bit more, before the artifacting becomes a serious problem. I don't think
> that's enough here.
>
> > Of course. An EXTEREMLY high-resolution of pitch-changing would have to
> > be used in order to ensure that artifacts are not present. Such is not
> > yet available.
>
> It's mathematically impossible to avoid the artifacts entirely, as the
> necessary information simply doesn't exist in the original waveform.
Its possible to keep the artifacts below a perceptible level, though.
Right?
>
> What might be possible is to extract general properties of the solar wind
> sound from a large number of samples, and use that to synthesize a
> solar-wind-like sound at audible frequencies.
>
> -- Ben
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Date: 22 Oct 2006 02:11:25
From: Ben Rudiak-Gould
Subject: Re: Increasing the pitch of solar sound without decrease playback
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Radium wrote:
> http://www.adobe.com/products/audition/overview2.html#kmhead3
>
> "Time and pitch processing: Change tempo without shifting pitch - or
> shift pitch without changing tempo - and never introduce audio
> artifacts."
They're exaggerating, as Spock would say. It does introduce artifacts. But
it works well as long as you don't push it too far.
> I wonder if this technique could enable astronomers to hear the sun
> "sing" with having to increase the speed of the data they record.
I think that you can generally raise the pitch by around an ave, maybe a
bit more, before the artifacting becomes a serious problem. I don't think
that's enough here.
> Of course. An EXTEREMLY high-resolution of pitch-changing would have to
> be used in order to ensure that artifacts are not present. Such is not
> yet available.
It's mathematically impossible to avoid the artifacts entirely, as the
necessary information simply doesn't exist in the original waveform.
What might be possible is to extract general properties of the solar wind
sound from a large number of samples, and use that to synthesize a
solar-wind-like sound at audible frequencies.
-- Ben
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Date: 22 Oct 2006 03:34:21
From: Charlotta
Subject: Re: Increasing the pitch of solar sound without decrease playback time?
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what I want to know is why you posted this to ....relativity?
Radium wrote:
> Hi:
>
> Adobe Audition seems to be able to change the pitch of an audio file
> without changing the speed at which it plays.
>
> http://www.adobe.com/products/audition/overview2.html#kmhead3
>
> "Time and pitch processing: Change tempo without shifting pitch - or
> shift pitch without changing tempo - and never introduce audio
> artifacts."
>
> I wonder if this technique could enable astronomers to hear the sun
> "sing" with having to increase the speed of the data they record. The
> sun's acoustic signals are way too low-pitched for humans to hear. So
> either the recording of the sun's acoustic signals has to be sped up
> until the pitch is high enough for humans to hear or the pitch itself
> needs to be changed using some intense processing [such as that of
> Adobe Auditon]. It seems that the former method is used instead of the
> latter. Why? If the audio software has sufficient abilities to increase
> the pitch of infrasonic signals to that in the human audio-range --
> without increase the playback speed -- then why isn't such a method
> used?
>
> An advatange I see is that if the infrasound if for 5 minutes,
> increasing the pitch won't decrease the amount of time of the
> recording.
>
> Of course. An EXTEREMLY high-resolution of pitch-changing would have to
> be used in order to ensure that artifacts are not present. Such is not
> yet available.
>
> Thanks,
>
> Radium
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