How do we listen to music(all instruments at a time)?

Discussion in 'General Electronics Chat' started by supermankid, Mar 23, 2014.

  1. supermankid

    Thread Starter Member

    May 26, 2013
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    Apologies if the question in not clear enough. I will try to be as clear as possible in my question. My question is as follows:

    When we hear the music, we hear all the small bits at a time very fast so it sounds smooth. Am I right?

    If so...in a song there are more than four different devices (guitar+drum+piano+voice)

    Then at one time(in one bit), it should contain these all sounds together.

    Does this mean that there is a new frequency(one single frequency) of sound which is combination of all guitar+drum+whatever present?
     
  2. Shagas

    Active Member

    May 13, 2013
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    Do you mean bit as in 'a little bit? " or as in a binary bit?
    Put your hand in front of you , and start moving it very slowly from left to right about 20 cm.
    Now also move your hand faster from left to right (5 cm) while still moving 20 cm slowly.
    Congratulations your hand movement contains two frequencies.
    You can use that notion to try explain your question.
    If you put the sound of an instrument into a spectral analyzer you will see that the sound consists of many many frequencies.
    I hope my analogy helped. Try going on youtube and looking for different animations like "wave superposition " , "modulation " , "sound spectrum" , " how speakers work " etc
     
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  3. GopherT

    AAC Fanatic!

    Nov 23, 2012
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    As music is played, each instrument makes its own frequency (note) but also a unique wave shape and intensity. They all eventually reach your ear and depending on distance and direction, the noises all create interference patterns with each other (constructive interference and destructive interference) to yield the final sounds that your brain interprets. In the end, your vibrating ear tissue can only be in one point in space at one time so it can only manage the sum of all sounds (the net value of the instantaneous waves that reach your ear.

    The same thing happens with your other ear. Because sound waves have a defines speed and frequency and higher frequencies are perceived as moe directional than low (and because your head is a good blockade dor sound) your two ears hear slightly different noises - especially when the sound is not in front of you)

    I may not have exactly answered your question but I hope so.
     
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  4. bertus

    Administrator

    Apr 5, 2008
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    Hello,

    The played music you are hearing is a complex mixture of sounds.
    Each sound on itself is a mixture of sines.

    Have a look on the following page on the ear and hearing:
    http://library.thinkquest.org/19537/

    There are also some applets to show you various topics of sounds.

    Bertus
     
  5. crutschow

    Expert

    Mar 14, 2008
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    The interesting thing is that the brain can listen to this single continuous stream of frequencies and be able to hear and recognize all the individual instrument types, sounds, and human voices as if they were separate. Now that's a real feat of signal processing. Let's see any machine try to do that.
     
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  6. Little Ghostman

    Member

    Jan 1, 2014
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    My dad ears have a mum's voice band pass filter :D
     
  7. GopherT

    AAC Fanatic!

    Nov 23, 2012
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    It seems that about half of the male population is able to do this.
     
  8. crutschow

    Expert

    Mar 14, 2008
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    My wife says I have a band-reject filter for her voice. ;)
     
  9. MrChips

    Moderator

    Oct 2, 2009
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    It's called MSI, Male Survival Instinct - learning to tune out in order to preserve your sanity.
     
  10. atferrari

    AAC Fanatic!

    Jan 6, 2004
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    The best I could implement was and All pass with just little delay.

    In due time I got bypassed permanently.
     
  11. JohnInTX

    Moderator

    Jun 26, 2012
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    A good book on this is How Music Works by John Powell. The author, a physicist and composer, does a nice job of combining the art and science of music including how the brain processes the complex sounds from many instruments playing together, why our hearing is logarithmic, the psychology of music and much more.
     
  12. Veracohr

    Well-Known Member

    Jan 3, 2011
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    I think you might be under a common misconception about digital audio. It's true that the audio in digital form is in discrete samples, but the process of converting digital audio to analog sound creates a continuous signal. It sounds smooth because it is: digital samples are converted to discrete-time analog signals, basically creating a stair-stepped analog signal, which is then filtered to remove the 'steps' and re-create the original analog sound.
     
  13. supermankid

    Thread Starter Member

    May 26, 2013
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    Wow, I am quite clear now. This idea of spectrum is convincing. I had the slightest doubt that it might contain a lot of frequencies superimposed. That means we can create a beautiful music consisting of all the instruments and voice if we can create those waves in some sort if program in computer. Amazing. Thanks to all good people :)
     
  14. wayneh

    Expert

    Sep 9, 2010
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    Just one more thing. It's worth understanding how your ear hears. It is an exquisite device (huge range) for detecting air pressure fluctuations, and converting that to nerve pulses. That is ALL it does. At any instant, it is seeing a single air pressure and creating a corresponding voltage in a nerve. It's your brain that does the rest, processing all the pulses. Pretty amazing that you can hear a 1000Hz tone and a 1002Hz tone at the same time, and easily perceive both of them as distinct tones. I'm not sure anyone knows how the brain does that. FFT?
     
  15. Veracohr

    Well-Known Member

    Jan 3, 2011
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    Not to mention amplitude sensitivity. We have something like a 140dB range from the lowest audible sound to the level of pain.
     
  16. Veracohr

    Well-Known Member

    Jan 3, 2011
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    If you hear them at the same time you're probably able to tell they're different because of the 2Hz beat frequency they would create. Alternate playing the two frequencies individually and it would probably be a lot harder to tell they were different.
     
  17. MrChips

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    Oct 2, 2009
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    The fourier transformation is performed in the cochlea in the inner ear.
    The cochlea itself is an FFT device and it is sensitive to frequencies.
     
  18. GopherT

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    Nov 23, 2012
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    You just made me look that up and what a cool concept. Thanks.

    The hairs on the cochlea seem to play a key role. Made me think that the hair in my nose and outer ear keep growing as I age. I wonder if the hair on the cochlea continues growing with age and makes human hears less sensitive to high frequencies as we age.
     
  19. MrChips

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    Oct 2, 2009
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    Eh? Maybe.
    I am deaf to anything above 3kHz.
    Fortunately my wife talks at 4kHz.
     
  20. Metalmann

    Active Member

    Dec 8, 2012
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    Relating to that, I used to be able to play, sing, and stay in time; while listening to someone shout into my ear what song they; (Audience), would like us to play next.:cool:
    Played in some request bands, too.

    As I get older, I find that my ears hear more low frequencies, more clearly. Which comes in real handy for a Bass Player.....:D

    Then, at rehearsal, I could shout out chord changes to a guitar/keyboard player. Don't know how the brain keeps up with all that information flying in and out all at once.

    The brain, is an amazing machine.........
     
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