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Air absorption feature working?

Spat
#1

Hi All!

I’m a little bit in doubt if I’m 100% completely retarted, or if the Air Absorption feature is a little bit ‘placebo’. I believe I hear no change when I play pink~ or noise~ through spat, leave a source in some coordinate, and activate / deactivate ‘Air Absorption’.

I get no result either, if I activate and move the source a tiny bit / deactivate and move the source a tiny bit.

A note to this: I experience that I have to move the source, after changing the ‘drop law’ from log > lin or vica versa. Don’t know if this is just a choice or ‘a bug’, but it would be cool that the source updates it self, when a change of parameter is done, instead of when it is updated with a new coordinate (in my opinion :slight_smile:

See you!
Lasse

#2

Hi Lasse,

First of all: could you (again) specify whether these issues affect the Ircam Tools Plugin or Spat for Max/MSP ? (or both)

Regarding air absorption: please be aware that this is somehow a subtle effect. Air absorption acts as a lowpass filter depending on the distance of the source.
It mainly filters frequencies above ~8-10 kHz. Also the rolloff is rather smooth, so if the source is too close (let’s say, less than 10 meters), you might not hear much difference.
To convince yourself: use white noise, disable the room effect (by setting the omni global gain to -60 dB), put the source far away (20m or more), adjust the source presence so that you can hear something, and then toggle the air absorption on and off. The high frequencies damping should be clear. If not, let me know.

Regarding drop law: indeed you might need to move the source after changing the drop law, so that everything gets updated.
Not really a bug nor a choice… long story. I’ll see if I can improve that.

Best,
T.

#3

Hi T!

Sorry for the delayed reply… I tried that thing about seeing other people… I decided that it seriously does not work for me. haha! ok… bad joke.

I tried on both max and vst - i have learned from my many questions that it is a good idea to try on max to be sure :slight_smile:

Here are two screenshots of what i did / what you told me. I still believe it doesn’t work (maybe it’s the viking ears that stopped working above 10k, but I guess it is still a little too soon).

air-ab-1.tiff (728 KB)

#4

Hi Lasse,

Thanks again for your feedback.
For some reason, air absorption and doppler are disabled for stereo sources (which is your case).
But I must admit I dont remember why I did that in the first place.
I’ll enable these features for the next release (next week).

T.

#5

Hi T!

Thanks a lot!

Is it possible you can notify flux so they can have the update for the VST too ?

Have a nice day :slight_smile:

Lasse