Half a croissant, on a plate, with a sign in front of it saying '50c'
h a l f b a k e r y
Renovating the wheel

idea: add, search, annotate, link, view, overview, recent, by name, random

meta: news, help, about, links, report a problem

account: browse anonymously, or get an account and write.



3D Audio

3D sounds using headphones.
(+1, -1)
  [vote for,

I don't want to spend extra amount of money for more speakers, that don't work when using certian applications just to sometimes get 3D sound.

Here is the experiment: model a approxamate human head with mics in the ears. Produce a known sound in different locations around the head (360deg on the xy, xz, & yz planes). Then find the differences in the sounds (wavelength, frequency, pitch, etc.)

Slightly edit sounds on the fly and play it through headphones. Depending on what "sound effect" you add determines where the sound seems to come from.

We now have a cheap way of creating 3D sound, now we need a 3D game to edit sounds on the fly.

Now, I don't know much about how humans are able to detect from which direction a sound is coming from, but this may still be a valid experiment. If not I'd at least like to know more about how sound direction is sensed.

Saxywolf, Jul 12 2001

Kunstkopf recording http://www.sfu.ca/s...udio/Kunstkopf.html
(Lit: "Artificial Head", from the dummy in whose ears the microphones are plugged.) [jutta, Jul 12 2001]

Dolby Headphone http://www.dolby.com/dolbyheadphone/
Surround sound on headphones. Claims to be usable on any headphones. [andrewm, Oct 04 2004]


       I do believe creatures such as A3D and EAX already do this.
sodapop3000, Jul 12 2001

       One of my biggest problems with using 2 mics alone or with a simple sound barrier is that how do you tell the difference between directly in front, behind, or above. The sound gets to the ears at the same time. The only explanation I can think of is that our ears make our hearing directional like mics facing slightly forward. Even then Whats the difference between directly above and below?
Saxywolf, Jul 12 2001

       In general this is called "binaural" recording.   

       Saxywolf: I'm not an expert: my understanding is that there are two ways. One way is, since our outer ears (pinna) are oddly and asymmetrically shaped, they affect the incoming sound in different ways depending on the direction the sound is coming from. The other way is, if you move your head slightly, the sound you hear will change slightly depending both on where it's coming from and how you moved your head, and your brain will put that info together. RodsTiger alludes to this.   

       Ever notice how hard it is to tell the direction that a brief, unexpected sound came from? But if the sound lasts for a short while, it's a lot easier.
wiml, Jul 12 2001

       Back in the 70's, during that brief period of Quadraphonic sound, they had headphones that had 4 drivers. Each ear had a driver in front of the ear facing back, and one behind the ear facing front. Sort of a brute force way of getting front/back perception. Binaural should work about as well.   

       (wiml correctly described the action of the pinna in modifying sound)
jtgd, Jun 04 2002

       baked. my dad built one of these when i was just a kid.
ironfroggy, Feb 22 2003

       I heard a CD recorded like this once; it was called Cyborgasm. It sounded 3D, if you sat in a dark room with your eyes closed. Some of the sounds, you could almost feel them.
edshepp, Feb 27 2003

       indeed, baked (about 35 years ago), but still very obscure.   

       [wiml] right on regarding the pinnae, but it goes even further. no two pinnae are alike, somewhat akin to fingerprints. therefore, a persons' brain develops sound localization "algorithms" based upon the unique properties of their own pinnae. experiments have been done in which people are given false pinnae make of silicone to wear, and it turns out their sound localization skills become nil. pretty wild.   

       what this means is the only way to make a true, perfect sounding binaural recording is to custom-match the recording to the listener. go around with tiny microphones in your ears, and then the recording will sound perfect to you. but not anyone else. :)   

       i've listened to high quality binarual recordings, and it's pretty amazing. not perfect, but of course, there's no photograph showing te exact setup of the recording studio, so i couldn't know exactly what was where.   

       binarual recording never really caught on because the amount of labor required to make a good binarual recording far outweighed the benefits of having a "true" 3D representation. most recordings are music, and most music is played with all instruments at pretty much the same altitude...
urbanmatador, Mar 26 2003


back: main index

business  computer  culture  fashion  food  halfbakery  home  other  product  public  science  sport  vehicle