Cochlear nonlinearities

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5 hours ago, Rt66indierock said:

 

Get me to 1% of the market for anything above CD quality because I can't get there.

 

I can't help you personally with your goal. For a non musician my brain is very close to a musician's. I can easily put myself in Lisner Auditorium when I listen to Waiting for Columbus.  

Love that album.  Saw Little Feat twice in concert just after they finished recording for that album.  Not in those venues, but that album does a good job of what it was like to hear them live at the time. 

 

MMMMmmmmmmm?  Is it available on MQA?  Hahahahahahaha?  Really need that super debluring for that album. 

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1 hour ago, wgscott said:

Outstanding album. (Much better than the studio stuff.)  I would have liked to have seen them live.

First time was 10th night of a 17 consecutive date stretch.  You wouldn't have known it.  They played 89 US dates and 6 Japanese dates that year.  I saw them 6 months later, and still just as good.  

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On 7/6/2019 at 7:40 AM, JanRSmit said:

Is this proven, or your assumption.?

Many years ago, audax had a tweeter going to over 40khz. We did a test plating the tweeter out of sight in a room and played a 30khz tone. When people came in the room for meetings, after a short while they became restless, sort of disturbed, but no clue as what caused it. Then after stopping playing, the restless behaviour dissapeared. I also remember Goldmund , just started then, referred to research by military dealing with human audibility of impulses, concluding that the audibility threshold is well above 20khz. 

Oh so the illusive proof of ultrasonics is restless people and secret military research.  Goldmund has been around since 1978.  Any updates since then?

 

The restless thing should be an easy test to perform.  Maybe a few people could repeat it with video of this restless behavior. 

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2 hours ago, jabbr said:

Tinnitus

http://www.tinnitusjournal.com/articles/tinnitus-relief-using-highfrequency-sound-via-the-hypersound-audio-system-10833.html

This is production of sound in the audible band via demodulated ultrasound.  Hardly indicative of ultrasound being audible except when being used to produced below 20 khz sound.  The use of bone conduction ultrasound is not new, and also doesn't indicate normal listening is able to hear ultrasound.  

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2 hours ago, jabbr said:

 

I’m not sure you are grokking the full implications of this. 

 

1) Yes it’s possible that, like but not the same as intermodulation distortion, that the mechanism of ultrasonic affect on the cochlea is via this “demodulation” effect — not exactly demodulation but essentially subharmonics. So an ultrasonic signal, via nonlinearities, results in a specific pattern of cochlear excitation. 

2) This pattern might be unique to the individual and specific individual’s response to specific frequencies. 

3) Thus there is no global transform that would allow someone to “reencode” ultrasonic information in the 20-20kHz range. The mapping from 20-40 kHz to 20-20 kHz — or 20-11kHz is presumably specific to the individual. 

4) Thus ultrasonic information is necessary to contain the full experience, as heard by a person. 

 

5) That said it might be possible to “get close” to reencoding 24/96 into 24/44 by modeling an “average” air / cochlear nonlinearity.

Sorry much too big a reach.  This isn't any explanation of how 96 khz would be better than 44.1 khz for music.  For one there is no consistent way that speakers respond to such frequencies.  Most don't have any appreciable response in the first place. 

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I'm in agreement with pkane here.  I'm not being dogmatic either.  It seems as if any credible info is a real stretch.  

 

If those higher bandwidths make a difference they must be very small to be this far down the road and not have clear repeatable evidence of it. The meta-study paper, which I'm not sure is selective enough in the tests it included, concluded a difference for higher sample rates vs standard was audible over thousands of responses 56% of the time. Over the 12,000 or so responses that is enough to say it is a for real difference.  But even then the difference is not large at only 50% null vs 56% real effect.  Most of the studies included had some heroic playback conditions with unusually wide bandwidth gear that applies to less than 1% or 2%% of normal high end audiophile systems.  And would apply to probably not even 1% of available recordings.  My current DAC can put out 25 times the bandwidth of my hearing.  So I guess I'm covered.