Questions and Answers

Q =What happens when the hair-like nerve dies?

A = We can’t hear sound that used to excite those positions.

Q = How often does the hair-like nerves send electrical signals to the brain?

A = Unknown, must be faster than the 20kHz λ (wavelength) a lot. Thick about CD sampling frequency, why does it use a minimum of 44.1kHz? Human are analogous, might be continuous.

Q = How does the brain process sound?

A = By integration and unknowns.

•Q = Do the brain process sound in time or in frequency domain?

A = Unknown, perhaps both or more.

Q = How long does the brain collect sound before processing it?

•A = It is estimated to be 35ms window. The small ear drum unable to pick up low frequency and this correlates with the equal loudness contour.

35ms wavelength - is in time domain representation - converting it to frequency -> 1/0.035 = 28.57Hz

•Q = Do the brain process sound in every 35ms jump?

•A = No, this would render humans incapable of changing decisions for every 35ms segment. It also suggests the brain is in a constant update. We also know humans are highly analogue, therefore cannot be using the digital jump.

Q = •If human hearing are to evolve, what needs to be changed?

•A = The brain’s adoption of integration time window for low frequency extension is one, apart from other thing.

•Q = The 35ms window? What kind of window is it? Is it a rectangular window? Or a trailing window?

A = No one knows what is the shape of the window, except that we know it is not digital hence not a rectangular window.

Suggestions have been made that full-hanning window is closest. This is true due to it's UFO shape nature. However the trailing edges on both ends are too sharp, which does not correlate with human analgoues, therefore the window may be rounded not only in the middle top and bottom, but also side edges are round too.

Unless the integration time is extremely long, then full-hanning window is applicable, but we know the integration time is only around 35ms, and that sound in continuous form of speech and music, is relatively too long in comparison, therefore a full-hanning it not entirely applicable.

Q = Does the shape of the window make a significant difference?

•A = YES extremely significant with every minor changes. (see all MLSSA window adaptation for example.)

1. The Human Ears

2. Disclaimer

3. Questions

4. How is sound created?

5. How do sound travel?

6. How loud is loud?

7. How does the ear work?

8. How does the ear work 2?

9. Hairlike Nerve Died

10. How to localize sound?

11. What do we listen for - to?

12. How do we listen?

13. How to differentiate level?

14. What sound can be heard or not?

15. Regular music frequencies area

16. Questions and Answers

17. Example of sound in Frequency Domain

18. Example of sound in Time Domain

19. One prove of human listening in Time Domain

20. Conclusion

21. A New Thought

22. Side notes

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