Notices
Results 1 to 13 of 13

Thread: Resonance frequency

  1. #1 Resonance frequency 
    Forum Masters Degree thyristor's Avatar
    Join Date
    Feb 2008
    Location
    Sweden
    Posts
    542
    Hi!
    Let's consider two similar guitar strings, one which is placed in a guitar and one placed "freely". If we snap the two strings in the same way, we will hear much stronger sound from the guitar than from the "freely" placed string. Now, I understand that this is due to resonance, but where does the additional energy actually come from? If we snap the strings in the same way, we have made an eauql "input" of energy to each string.


    373 13231-mbm-13231 373
    Reply With Quote  
     

  2.  
     

  3. #2  
    Forum Freshman
    Join Date
    Sep 2009
    Posts
    8
    True, but in the first case more of the energy is converted into sound, while in the second more energy is converted to kinetic energy. Unless I misunderstood 'freely'? (Mind you, this really isn't my area of expertise, so feel free to correct me if I'm wrong.)


    Reply With Quote  
     

  4. #3 Re: Resonance frequency 
    . DrRocket's Avatar
    Join Date
    Aug 2008
    Posts
    5,486
    Quote Originally Posted by thyristor
    Hi!
    Let's consider two similar guitar strings, one which is placed in a guitar and one placed "freely". If we snap the two strings in the same way, we will hear much stronger sound from the guitar than from the "freely" placed string. Now, I understand that this is due to resonance, but where does the additional energy actually come from? If we snap the strings in the same way, we have made an eauql "input" of energy to each string.
    It is a matter of local intensity not total energy. The energy input to the strings is the same and all of that energy is eventually converted into sound energy plus a little heat in the strings due to internal friction.

    But the body of the guitar creates a resonance that results in a local amplification of the sound waves -- basically keeps some of the sound from dispersing as quickly.
    Reply With Quote  
     

  5. #4  
    Forum Freshman
    Join Date
    May 2010
    Posts
    98
    what happens is that with the free string only maybe about 25% of the sound is actually going to your ears and with the string in the giutar the chamber behind the giuter (and the fact thate there is wood right behind the string) this materiel reflects the sound waves made back out making more of them stike your ear.
    Once a door is opened it never truly closes
    Once a door is closed new ones are open
    Two concepts forever intwined it is you decision to make them for the better or the worse.

    Being invisble lets you run away from pain
    Being visible gives you irraplacable experiences.
    Reply With Quote  
     

  6. #5  
    Forum Junior
    Join Date
    Dec 2009
    Location
    New England
    Posts
    223
    The free string doesn't get a hold of as much air as the guitar surfaces provide in order to apply vibrational motion to launch air-born sound.
    "Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense." --Buddha (563BC-483BC)
    Reply With Quote  
     

  7. #6  
    . DrRocket's Avatar
    Join Date
    Aug 2008
    Posts
    5,486
    Quote Originally Posted by dalemiller
    The free string doesn't get a hold of as much air as the guitar surfaces provide in order to apply vibrational motion to launch air-born sound.
    gibberish
    Reply With Quote  
     

  8. #7  
    Forum Masters Degree Twit of wit's Avatar
    Join Date
    Jan 2010
    Posts
    553
    Quote Originally Posted by DrRocket
    Quote Originally Posted by dalemiller
    The free string doesn't get a hold of as much air as the guitar surfaces provide in order to apply vibrational motion to launch air-born sound.
    gibberish
    Wrong!
    Reply With Quote  
     

  9. #8  
    . DrRocket's Avatar
    Join Date
    Aug 2008
    Posts
    5,486
    Quote Originally Posted by Twit of wit
    Quote Originally Posted by DrRocket
    Quote Originally Posted by dalemiller
    The free string doesn't get a hold of as much air as the guitar surfaces provide in order to apply vibrational motion to launch air-born sound.
    gibberish
    Wrong!
    \

    hardly
    Reply With Quote  
     

  10. #9  
    Forum Masters Degree Twit of wit's Avatar
    Join Date
    Jan 2010
    Posts
    553
    Quote Originally Posted by DrRocket
    Quote Originally Posted by Twit of wit
    Quote Originally Posted by DrRocket
    Quote Originally Posted by dalemiller
    The free string doesn't get a hold of as much air as the guitar surfaces provide in order to apply vibrational motion to launch air-born sound.
    gibberish
    Wrong!
    \

    hardly
    The string is vibrating, but moves little air, as it is too thin. The body has a large surface, so it can move move much more air.
    http://www.phys.unsw.edu.au/~jw/guitarintro.html
    Reply With Quote  
     

  11. #10  
    . DrRocket's Avatar
    Join Date
    Aug 2008
    Posts
    5,486
    Quote Originally Posted by Twit of wit
    Quote Originally Posted by DrRocket
    Quote Originally Posted by Twit of wit
    Quote Originally Posted by DrRocket
    Quote Originally Posted by dalemiller
    The free string doesn't get a hold of as much air as the guitar surfaces provide in order to apply vibrational motion to launch air-born sound.
    gibberish
    Wrong!
    \

    hardly
    The string is vibrating, but moves little air, as it is too thin. The body has a large surface, so it can move move much more air.
    http://www.phys.unsw.edu.au/~jw/guitarintro.html
    Don't believe everything that you read on the internet.
    Reply With Quote  
     

  12. #11  
    Forum Masters Degree Twit of wit's Avatar
    Join Date
    Jan 2010
    Posts
    553
    Quote Originally Posted by DrRocket

    Don't believe everything that you read on the internet.
    I don't but this makes perfect sense.
    Reply With Quote  
     

  13. #12 Re: Resonance frequency 
    Forum Junior
    Join Date
    Dec 2009
    Location
    New England
    Posts
    223
    Quote Originally Posted by DrRocket
    Quote Originally Posted by thyristor
    Hi!
    Let's consider two similar guitar strings, one which is placed in a guitar and one placed "freely". If we snap the two strings in the same way, we will hear much stronger sound from the guitar than from the "freely" placed string. Now, I understand that this is due to resonance, but where does the additional energy actually come from? If we snap the strings in the same way, we have made an eauql "input" of energy to each string.
    It is a matter of local intensity not total energy. The energy input to the strings is the same and all of that energy is eventually converted into sound energy plus a little heat in the strings due to internal friction.

    But the body of the guitar creates a resonance that results in a local amplification of the sound waves -- basically keeps some of the sound from dispersing as quickly.
    Wrong. Resonance starts and stops with the guitar string. We cannot presume that the body of the guitar is resonant to all of the sounds produced within the guitar. Competent technical discussion becomes further distressed by implication that sound wave amplification is accomplished without provision of a power supply.

    It is simply that more sound energy is distributed into the air when more of the energy has been converted into such form.
    "Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense." --Buddha (563BC-483BC)
    Reply With Quote  
     

  14. #13  
    Forum Junior
    Join Date
    Dec 2009
    Location
    New England
    Posts
    223
    Quote Originally Posted by DrRocket
    Quote Originally Posted by dalemiller
    The free string doesn't get a hold of as much air as the guitar surfaces provide in order to apply vibrational motion to launch air-born sound.
    gibberish
    It does not seem constructive, scientific, or within the normal constraints of decency to counter someone's statement with nothing but a malicious slur. Is the man jealous?
    "Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense." --Buddha (563BC-483BC)
    Reply With Quote  
     

Bookmarks
Bookmarks
Posting Permissions
  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •