Well, actually, you only need two channels for surround sound. There are quite a few factors to define where a sound source is located. As far as the horizontal plane is concerned, the location is determined by two factors. First the time difference between the arrival at the ears is taken into account (makes for a astonishigly small time scale, especially with higher frequencies, but the brain can handle it). Then, the volume difference is evaluated: If a sound source is to your left, the signal is louder in your left ear then in your right.
As far as vertical position is concerned, the form of your outer ear is relevant. Dependent on the position of the sound source, different frequency bands are attenuated or amplified. These are the so called HRTFs (Head Related Transfer Functions).
Using this information, you can filter your sound sources with the according transfer functions and get a really realistic result. I once was able to try out such a system as part of a course here at university. It simulated 5 sound sources in a room and there was a head-tracker mounted on the headphones. So if you turned your head left, the drums would become louder. Pretty cool stuff!:-)
We did some experiments with a fuel cell from Heliocentris. The fuel cell itself was pretty cool. (We had the one with 20 W max. power) Problem is that the prices are pretty hefty and you usually get the fuel cell only, so you have to come up with some way to supply hydrogen etc. Playing with hydrogen also is not a thing I would try at home. Besides, I'm not sure they sell to end-customers. But contacting them may be worth a try...
Good luck!
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Well, actually, you only need two channels for surround sound. There are quite a few factors to define where a sound source is located. As far as the horizontal plane is concerned, the location is determined by two factors. First the time difference between the arrival at the ears is taken into account (makes for a astonishigly small time scale, especially with higher frequencies, but the brain can handle it). Then, the volume difference is evaluated: If a sound source is to your left, the signal is louder in your left ear then in your right. As far as vertical position is concerned, the form of your outer ear is relevant. Dependent on the position of the sound source, different frequency bands are attenuated or amplified. These are the so called HRTFs (Head Related Transfer Functions). Using this information, you can filter your sound sources with the according transfer functions and get a really realistic result. I once was able to try out such a system as part of a course here at university. It simulated 5 sound sources in a room and there was a head-tracker mounted on the headphones. So if you turned your head left, the drums would become louder. Pretty cool stuff! :-)
We did some experiments with a fuel cell from Heliocentris. The fuel cell itself was pretty cool. (We had the one with 20 W max. power) Problem is that the prices are pretty hefty and you usually get the fuel cell only, so you have to come up with some way to supply hydrogen etc. Playing with hydrogen also is not a thing I would try at home. Besides, I'm not sure they sell to end-customers. But contacting them may be worth a try... Good luck!