[SOLVED] Positional Sound Artifacts

Hi guys!

when activating the ‘positional sound’ and moving the camera around there are some sound artifacts appearing. I can reproduce this issue. Is it something with my configuration oder maybe the mp4 format causing this?

https://playcanvas.com/editor/scene/1012268

It’s not a real dealbreaker for me but I would like to know if have a wrong setup. I tried with a couple of different files and some seem to work better than others.

Kind regards
-Sebastian

I forked your project and then exported test.mp4 so that I could re-encode it. I re-encoded to 44.1 khz and omitted the video on the re-encode. I suspect that the dropping of the video is the main benefit in that drops the file size in half. The re-encode plays smoothly without any of the little pop/scratch sounds I heard from the original.

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So I tried a version with no video but at the original 48khz sampling and got the static back So I added the video back but sampled at 44.1 khz and the audio cleaned up again.

And there is another factor. I changed the volume from 0.26 to 0.25. That seems to also help

So the two factors that seem to affect the noise are the sampling rate and the volume. Setting the volume to 0.25 and the sampling rate to 44.1 khz in the audio file gives me much cleaner audio. Having the video frames along for the ride doesn’t seem to be a factor.

It isn’t perfect, but it is clearly better than the original. I still get a very occasional pops when moving the view. And I also get a very muted and subtle motor boat sound when I rotate the view quickly. It is much easier to notice when the box is behind the camera view. My bet is that the pops are Playcanvas/browser/player artifacts while the “motor boat” is actually system electrical noise induced into my very cheap sound card from the GPU or something similar.

Anyway, much cleaner at 44.1 khz and 0.25 volume.

Note: I re-encoded using Adobe Media encoder. Message me your email if you don’t have an easy way to re-encode and I can send you the re-encoded files.

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Hey thanks for the digging @wturber, greatly appreciated!

When I load the file test.mp4 in Audacity it gives me a sample rate of 44.1 kHz. Windows also says the file is already encoded in 44.1.

Hmmmm, maybe I am overlooking something. I will send you my email :slight_smile:

OK. That’s weird. I went back and re-loaded the test.mp4 and it is 44.1 khz. So what I think happened was that the output defaulted to 48khz and the first re-encode I did was to get rid of the video. So from there I must have just been assuming a 48khz source.

But I did load and reload the original and the better audio followed the new files re-encoded at 44.1khz. So it may have more to do with the encoder than the sample rate? I see your DM and will send you the files.

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Hey @wturber,

you sent me the mp3 file and the sound artifacts are almost all gone. Great job and thanks for analyzing and helping me out! Would have never thought of the sample rate :sweat_smile:

Cheers :beers:

No problem. But it probably wasn’t the sample rate as much as maybe the encoder. Still a bit of a mystery to me.