21 Jul
2010
21 Jul
'10
9:06 p.m.
Continuation of talk from
Re: [LAD] Floating point processing and high dynamic range audio
Simply Subject line no longer described the actual content.
On 2010.07.21. 20:19, Jörn Nettingsmeier wrote:
On 07/21/2010 08:56 PM, JohnLM wrote:
Thanks! Though this is quite sophisticated. I currently only worry about
sound (pressure) level. I will try to implement the rest when the
current code actually works.
Well I have a set of (omidirectional) point sources.
The code currently has no information whenever given space is open or
enclosed. (I guess open or empty space is implied then)
As much as I can understand the sound pressure is inversely linearly
correlated to distance. p~(1/d) or p=k*(1/d) where k is currently
undefined constant coefficient.
What's the thing about far and near fields?
On Wed, Jul 21, 2010 at 2:01 PM,<fons(a)kokkinizita.net> wrote:
If I code program to handle attenuation of sounds
depending on their
source (emitter) position in virtual 3D space, I guess then there's no
simple way to relate the effect to real world.
How this is usually handled?
you reduce the level with distance (amount depends on whether you are in the near or far
field and whether you have a point, line or planar source), and attenuate the high
frequencies to simulate air damping. if you're in an enclosed space, you'd also
want to take into account the dry-to-reverb ratio, and ideally simulate correct early
reflections. An audio signal represents pressure variation as a
function of
time. Multiplying it by two will give 2 times the pressure,
and 4 times the power. The subjective result is another matter.
Ummm... is it sound pressure or sound pressure level? Or it doesn't
matter? (are they equivalent?)
On 2010.07.21. 20:40, Ralf Mardorf wrote:
I guess the transit time issue for analog isn't
solved. When I worked
for Brauner we and SPL developed a surround microphone + SPL mixing
console. IMO it's pure bullshit.
http://audio.uni-lueneburg.de/seminarwebseiten/audiomedien/frst/material/IC…
http://audio.uni-lueneburg.de/seminarwebseiten/audiomedien/frst/material/as…
Perhaps today there is math for virtual effects, I don't know, but I
would be very sceptic.
I'm sure any digital alogrithm are far from perfect to represent the
acoustic attenuation (and related) effects like in real world. But it
just need to be close enough.
Ummm... I somehow fail to see how the microphone rig is related to this.
