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An externally hosted image should be here but it was not working when we last tested it.
So this picture is making the rounds on Facebook.
I can't help but notice the asymmetry of the first waveform. I did some searching and found out that the asymmetry of the waveform is indicative of even harmonic distortion. Can any audio engineers here give a hint of what may have caused it?
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The human voice is asymmetrical. We speak and sing while we're exhaling. Pretty much the same for horns. They produce their sound while the player is exhaling.
When closer to the microphone, the asymmetry is greater.
When closer to the microphone, the asymmetry is greater.
Hi,
Nothing to do with even harmonic distortion unless its very severe,
and that would affect all the plots equally. FWIW if you measure
the human speaking /singing voice down to DC it is notably
assymetric, very unsurprising if you think about it.
I'd say its the difference between just saying "I do" in a relaxed
manner and saying "I do" preceded by an intake of breath and
consequent exhalation creating the DC waveform offset.
rgds, sreten.
Very likely in real terms the traces are upside down.
Nothing to do with even harmonic distortion unless its very severe,
and that would affect all the plots equally. FWIW if you measure
the human speaking /singing voice down to DC it is notably
assymetric, very unsurprising if you think about it.
I'd say its the difference between just saying "I do" in a relaxed
manner and saying "I do" preceded by an intake of breath and
consequent exhalation creating the DC waveform offset.
rgds, sreten.
Very likely in real terms the traces are upside down.
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Mathematically, asymmetric waveforms are caused by the presence of even harmonics. Whether these are caused by distortion or overtones from the original instrument is immaterial. Very few amplifiers and very few instruments produce only odd harmonics, so waveform asymmetry is normal although it may sometimes be too small to be obvious.
Harmonics have absolutely nothing to do with the asymmetry of a waveform.
Harmonic energy will appear equally on the positive and negative portions of the waveform.
As a retired Broadcast Engineer, I am familiar with audio asymmetry. AM Broadcast audio processors have included phase scramblers (all-pass filters) for decades. Prior to the introduction of the filter, it was very important that the studio microphones be 'phased' properly so that the highest waveform amplitude was in the positive direction.
As I stated in an earlier post. The human voice is naturally asymmetrical.
Harmonic energy will appear equally on the positive and negative portions of the waveform.
As a retired Broadcast Engineer, I am familiar with audio asymmetry. AM Broadcast audio processors have included phase scramblers (all-pass filters) for decades. Prior to the introduction of the filter, it was very important that the studio microphones be 'phased' properly so that the highest waveform amplitude was in the positive direction.
As I stated in an earlier post. The human voice is naturally asymmetrical.
Complete nonsense.Frank Berry said:
True for odd harmonics. Untrue for even harmonics.
But quite unfamiliar with the mathematical origin of it?
Which necessarily means that the human voice naturally includes significant even harmonics.
Sir. You are a very rude know-it-all.
You are also wrong.
Harmonics of any sine wave will be equal on both + and -
Harmonics do not cause asymmetry.
You are also wrong.
Harmonics of any sine wave will be equal on both + and -
Harmonics do not cause asymmetry.
"There is more energy available for the compression side of the waveform than the rarefaction side."
__________________________________________________Rick..........
__________________________________________________Rick..........
No, asymmetry is caused by harmonics. Although the integrated energy will be the same on either side of the zero crossing (assuming DC has been removed), the waveform shape will not be the same. You can demonstrate that for yourself by using Excel, taking a sine wave, adding in (say) 20% second harmonic, then graphing the result. Likewise, you can take a sine wave, just clip on one side, then perform a Fourier transform.
Bickering aside, as stated above the voice is asymmetric. You see this all the time in waveform displays of the voice. Nothing unusual. With some free software and a mic, you can see this for yourself. Audacity is a good start.
Don't see it with H2 or H3 added in up to 50% of the fundamental level. Wonder if the software is removing the offset?
If you shift the phase of the second harmonic by 90 degrees, you'll see the asymetry.
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