Hi All, Is there a formula or mathematical concept to find the resonant frequencies in a sound wave? Thanks Rael
Formula to Find Resonant Frequencies?
Started by ●March 12, 2011
Reply by ●March 12, 20112011-03-12
On Mar 13, 12:01�pm, Raeldor <rael...@gmail.com> wrote:> Hi All, > > Is there a formula or mathematical concept to find the resonant > frequencies in a sound wave? > > Thanks > RaelHas to resonate against something. We need more info. A sound wave can resonate in a small room and such like. Please be more clear.
Reply by ●March 12, 20112011-03-12
On Mar 12, 5:27�pm, HardySpicer <gyansor...@gmail.com> wrote:> On Mar 13, 12:01�pm, Raeldor <rael...@gmail.com> wrote: > > > Hi All, > > > Is there a formula or mathematical concept to find the resonant > > frequencies in a sound wave? > > > Thanks > > Rael > > Has to resonate against something. We need more info. A sound wave can > resonate in a small room > and such like. Please be more clear.Do I need to know what it's resonating against in order to find the frequency? What if I want to find the resonant frequencies in a small room vs a large hall for example? Thanks Rael
Reply by ●March 12, 20112011-03-12
On Sat, 12 Mar 2011 15:01:43 -0800, Raeldor wrote:> Hi All, > > Is there a formula or mathematical concept to find the resonant > frequencies in a sound wave?The phrase "resonant frequencies in a sound wave" does not compute. A resonance -- and therefore a resonant frequency -- is a characteristic of a physical system such as a structure, a room, a musical instrument, etc. So: Are you trying to find the resonant frequency of some physical system? Or are you trying to find tones in a sound? Or what? -- http://www.wescottdesign.com
Reply by ●March 13, 20112011-03-13
Raeldor <raeldor@gmail.com> wrote: (snip, someone wrote)>> Has to resonate against something. We need more info. A sound wave can >> resonate in a small room and such like. Please be more clear.> Do I need to know what it's resonating against in order to find the > frequency? What if I want to find the resonant frequencies in a small > room vs a large hall for example?The resonance are in the room, not in the sound. That is what was confusing to people. Depending on the wall material, there may be some effect, but mostly you just need the size of the room and the speed of sound. For a long tube (like many musical instruments), either closed at both ends or open at both ends, the fundamental wavelength is twice the length of the tube. For a room with solid walls, there should be resonance with half wavelength equal to the room dimensions (height, width, length), and the various diagonals. The frequency is then the speed of sound divided by the wavelength. -- glen
Reply by ●March 13, 20112011-03-13
On Sat, 12 Mar 2011 15:01:43 -0800 (PST), Raeldor <raeldor@gmail.com> wrote:>Hi All, > >Is there a formula or mathematical concept to find the resonant >frequencies in a sound wave? > >Thanks >RaelHello Rael, Like the other guys said here, the wording of your question doesn't make sense. Perhaps searching the web for information on vibrating guitar strings will answer the question that you're trying to ask. Good Luck, [-Rick-]
Reply by ●March 13, 20112011-03-13
On Mar 13, 4:33�am, Rick Lyons <R.Lyons@_BOGUS_ieee.org> wrote:> On Sat, 12 Mar 2011 15:01:43 -0800 (PST), Raeldor <rael...@gmail.com> > wrote: > > >Hi All, > > >Is there a formula or mathematical concept to find the resonant > >frequencies in a sound wave? > > >Thanks > >Rael > > Hello Rael, > � �Like the other guys said here, the > wording of your question doesn't make > sense. �Perhaps searching the web > for information on vibrating guitar strings > will answer the question that you're > trying to ask. > > Good Luck, > [-Rick-]Thanks guys. I'll do little more research. I thought a clean sound (sine wave) would reverberate at certain frequencies depending on the size, space of the room, but I guess I'm confused. Thanks for all you help though. Regards Rael
Reply by ●March 13, 20112011-03-13
On Sun, 13 Mar 2011 09:06:49 -0700, Raeldor wrote:> On Mar 13, 4:33 am, Rick Lyons <R.Lyons@_BOGUS_ieee.org> wrote: >> On Sat, 12 Mar 2011 15:01:43 -0800 (PST), Raeldor <rael...@gmail.com> >> wrote: >> >> >Hi All, >> >> >Is there a formula or mathematical concept to find the resonant >> >frequencies in a sound wave? >> >> >Thanks >> >Rael >> >> Hello Rael, >> Like the other guys said here, the >> wording of your question doesn't make sense. Perhaps searching the web >> for information on vibrating guitar strings will answer the question >> that you're >> trying to ask. >> >> Good Luck, >> [-Rick-] > > Thanks guys. I'll do little more research. I thought a clean sound > (sine wave) would reverberate at certain frequencies depending on the > size, space of the room, but I guess I'm confused. Thanks for all you > help though.Well, it can -- but you were asking for ways to find the resonance _in a signal_, and that doesn't make sense. It sounds like you want to find the resonance _in a room_, which (a) does make sense, and (b) has a lot of practical interest, so there's folks who actually know how to do it. If you have a speaker, a microphone, some time, and a computer, you can generate a signal, apply it to the speaker, and see what comes back to the microphone. You can use this to find the resonances (or eigenvalues, if you want to get fancy) of the room. Exactly _what_ signal you apply to the speaker, and _how_ you process the signal that comes back is question that's generated significant study over the years. -- http://www.wescottdesign.com
Reply by ●March 13, 20112011-03-13
Tim's setup -- a microphone, amplifier, and speaker -- provides an easy to find the dominant resonance. Just turn the gain up until acoustic feedback makes the system howl. The frequency of the howl is the strongest resonance. A notch filter that blocks that frequency will show the next weaker resonance. Jerry -- Engineering is the art of making what you want from things you can get.
Reply by ●March 13, 20112011-03-13
On Mar 13, 12:06�pm, Raeldor <rael...@gmail.com> wrote:> On Mar 13, 4:33�am, Rick Lyons <R.Lyons@_BOGUS_ieee.org> wrote: > > > > > On Sat, 12 Mar 2011 15:01:43 -0800 (PST), Raeldor <rael...@gmail.com> > > wrote: > > > >Hi All, > > > >Is there a formula or mathematical concept to find the resonant > > >frequencies in a sound wave? > > > >Thanks > > >Rael > > > Hello Rael, > > � �Like the other guys said here, the > > wording of your question doesn't make > > sense. �Perhaps searching the web > > for information on vibrating guitar strings > > will answer the question that you're > > trying to ask. > > > Good Luck, > > [-Rick-] > > Thanks guys. �I'll do little more research. �I thought a clean sound > (sine wave) would reverberate at certain frequencies depending on the > size, space of the room, but I guess I'm confused. �Thanks for all you > help though. > > Regards > Raeltry searching for "room mode" or "room resonance" Mark
