26 May
2004
26 May
'04
9:25 p.m.
On tor, 2004-05-20 at 11:59, Joern Nettingsmeier wrote:
Jens M Andreasen wrote:
I went to ambisonic and read the FAQ. I do not
agree with them when they
say that 2-channel stereo is only good for imaging between the speakers.
It is possible by using phase differences (and the assumption that
people are not living in sound-dead laboratories) to project sounds
outside of the stereo-field.
I did not find anything either to support that 4-channel is superior to
7-channel ... Maybe I was not looking hard enough ??
/jens
not superior, but equivalent, less snake-oil-infested,
cheaper, more
general and more elegant. ahem, yes, superior :-D
OK, point taken! :-)
you can express any spatial sound with just 4
channels, where one is
the mono component, and 3 are the x, y, and z-axis difference
signals (similar to m/s stereo).
you can then render it to any speaker layout you want.
Say I have two speakers hanging quite high left/right and a center
speaker even higher above the stage. These three speakers are "flewn"
slightly out over the audience. If you want, you can place speakers
somewhat to the back on the left/right balcony as well, together with
lights. This layout sounds more like a theater than a cinema, right?
Say, I would like music to be rendered left/right, sound-effects to be
wrapped around 180° and dialogue rendered only center. Would that be
possible by using ambiosonic?
The most important part being that the dialogue would really appear to
come from a single point, so as not to clutter the focus with several
speakers being slightly out of phase, each adding their own delay
pattern unrelated to an illusional center-panned position.
imnsho all those n.1 surround techniques (where n is defined as the
number of speakers you have or want to afford plus any positive
integer greater than one) are money-making schemes. anything above
5.1 in one plane is plain stupid (even the center is not necessary
in theory, although it makes the job for the mix engineer a lot easier).
and the mutually incompatible encoding formats are not helping either...
and as to encoding anything outside the line between the speakers in
stereo, well, it just does not work very well. it's ok for the
occasional "wow, cool" effect, but for not much else. all those
nifty little tricks have very small sweet spots and fall apart as
soon as you move just a little, and those oh-so-cool 3d phasing
effects completely and utterly wreck the low end in practice.
It works fairly well for closely spaced speakers, like stereo-TV or
"ghetto-blaster".
/jens