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Frequency-shaped background noise generators

mynoise.net

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Re: Frequency-shaped background noise generators

#81

Post by kaoD »

audiosampling wrote: post #40
groundCode wrote: post #30

Great resource thanks! I love the Tibetan chanting. Would love something that subtley changes the sliders over time.

Hey, this is what the "Motion" buttons does, although the slider do not move in a visible way.

IMHO the slider should move, both to provide visual feedback and to make the effect less subtle.

Re: Frequency-shaped background noise generators

#82

Post by kaoD »

kintamanimatt wrote: post #53
calibwam wrote: post #41

Earlier quoted context omitted.

Thanks for doing this, I'm going to use this page a lot, I think. But have you thought about open sourcing some, if not all of the code? With the source code out on for instance github, a lot of people could help you out wherever you feel your own skills come to short.

If it were me, I'd not open source this. Common tools that are used to build other things generally are, such as a compiler or VCS, but an actual finished product, not so much. Open sourcing this would be like Github open sourcing github.com, rather than just a handful of common tools they built to create github that might be useful to others. Open source has a time and a place, but some things, like finished website…

Well, he could opensource the audio components, especially the multiplatform/browser bits.

Re: Frequency-shaped background noise generators

#83

Post by conflagration »

The sounds are great by themselves, but I had the most fun layering different generators by opening several tabs. I played around with the EQ and made something sounding very close to Biosphere with 4 parallel tabs. It really felt like the tracks were synchronized to fit into each other. Great work!

Re: Frequency-shaped background noise generators

#85

Post by kaoD »

theatraine wrote: post #26
lost-theory wrote: post #10

Earlier quoted context omitted.

It loads 20 or so ogg audio files like this: http://mynoise.net/Data/OSMOSIS/7a.ogg Then I'm guessing the EQ controls the volume. So no it doesn't generate / stream anything to you server-side.

Right, the EQ controls the volume of each of the 10 (each one corresponds to a slider) sounds. (Every sound has been previously decomposed into its frequency components.) The Web Audio API is used for browsers that have it present, else HTML5 audio elements are used. The slider just adjusts the volume of the sound (exponentially of course!), leading to an equalizer effect with no filtering required. (Garnered from lo…

You could filter it yourself with a bit of DSP knowledge. I've seen this approach working effectively in Firefox without Web Audio API.

Impulse filters are easy to implement, e.g. an averaging low pass filter (or at least I think so, I'm no DSP expert):

  out(t) = 1/sum(a) * (a_1 * in(t) + a_2 * in(t-1) + ... + a_n * in(t-n+1))
Where "a" is a vector of constant coefficents.

You could even use FFT to modulate the bands separately, e.g.:

  Sample -> FFT -> Filtering -> FFTi -> Output

Re: Frequency-shaped background noise generators

#88

Post by kaoD »

audiosampling wrote: post #87
kaoD wrote: post #84

Nice job! Being able to share custom presets would be cool.

It's possible. Just follow the link "Save Your Current Slider Settings" then the URL. I should make it more obvious though, you are right.

Oh, nice! I'd put it closer to the sliders and make it clear you can share the saved settings.

I'd also let the user edit it without clicking anywhere. Right now clicking edit resets the sliders too :(

Re: Frequency-shaped background noise generators

#89

Post by shmerl »

Interesting, on Linux, PulseAudio shows many channels in the mixer (for ALSA plugin in Firefox), when the noise page is opened.

By the way the site mentions using OGG (I guess Vorbis) playback. How does it work in crippled browsers like mobile Safari, which don't support Vorbis?

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