Human Hearing

Interesting article on the sensitivity of human hearing.

Human hearing beats the Fourier uncertainty principle

A bit related....

During the voicing of components, I participated on a panel that consistently and repeatedly identified changes in frequency response of otherwise identical components by as small as 3 millibels. Subsequent testing with others revealed the human ability to identify smaller changes. This is A/B testing switching back and forth between components.

I think there is a discussion of these specific tests (without naming the participants) on the Herron Audio web site.
 

jcx

Member
2003-02-17 7:38 pm
..
Typical sensational science journalism/strawman version Psycoacoustics, Signal Theory

mentioned in the Blowtorch thread as well - eye catching title ends up not saying what many audiophiles would like to believe

read carefully - they quickly backpedal from the implied significance of the headline:

Since researchers have known for a long time about the cochlea's nonlinearities, the current results are not quite as surprising as they would otherwise be. "It is and it is not [surprising]," Magnasco told Phys.org. "We were surprised, yet we expected this to happen. The thing is, mathematically the possibility existed all along. There's a theorem that asserts uncertainty is only obeyed by linear operators (like the linear operators of quantum mechanics). Now there's five decades of careful documentation of just how nastily nonlinear the cochlea is, but it is not evident how any of the cochlea's nonlinearities contributes to enhancing time-frequency acuity. We now know our results imply that some of those nonlinearities have the purpose of sharpening acuity beyond the naïve linear limits.

Read more at: Human hearing beats the Fourier uncertainty principle

when they show the Cramer-Rao boundary for the stimulus on the same plot we can get excited if humean hearing beats a Signal Theory/Statistical Information Theory limit pointed out >50 years ago
 
Last edited:
That's true, but how do we know we're actually hearing what someone else hears? Our perception of a particular sound / pitch / transient is shaped by many factors including the shape of our outer ear, irregularities in the ear canal, the last concert we attended and if we drive our cars with the windows open (and a lot more).

That said, hearing sensitivity will also vary with the individual. But the sensitivity exists nonetheless and IMO it is much greater than most people think.
 

jcx

Member
2003-02-17 7:38 pm
..
human hearing limits with music have been explored in much greater depth in the past decade by those designing, tuning lossy codecs

encoding <20% of the Shannon-Hartley Channel capacity information of RedBook CD in only ~6-7 bits mantissa per critical band is "transparent" - to the point that public trials have been abandoned for higher bit rates since no statistically valid information was being seen
musically uncommon "killer samples", extensive training on the specific codec's errors and lower than typical home background noise listening setups is needed to hear differences at higher bit rates and better lossy codecs today
 
Last edited:
I believe that there is a difference in LISTENING (not necessarily hearing) between "the pubic" and audiophiles. That's why many of those lossy codecs are NOT transparent to audiophiles but perfectly acceptable to "the public." I also think that the audible difference between some high end components is such that "the pubic" can't tell (or don't listen for) the difference.
 

jcx

Member
2003-02-17 7:38 pm
..
lets see some of these audiophiles post foobar ABX 20/20 of music @ >256kb then - modern codecs, last few years tunings

really the differences today are extremely small, even when detected in ABX "better"/original isn't always clear

OGG, AAC, even WMA today are't the same as MP3 in early 2000
 
My two pennyworth is that I often see the ear brain relationship over simplified. The biological mechanism of the ear although remarkable, is pretty unsophisticated. The brain is the by far the most important part of our hearing mechanism. It does an incredible amount of processing to build the real time model of a sound field in our consciousness.

The enormously capable pattern recognition machine between our ears is subject to different perceptions and influences for each individual. Experience, environment, culture are all constantly changing, and all have a bearing on how we can perceive sound. There are areas of broad commonality between us but no absolute answers can be found here. We all perceive sound differently. Any research must be seen in that context.