Quadrophonic sound

Dear all,

Here, in Uruguay, we are carrying on a workshop on Physical Computing (fancy name), but have yet to decide which tools we’ll be using…

I’d like the students to use OpenFrameorks as I believe is a more general approach and so they will get the best out of the workshop… but the project we’re working on needs to output quadraphonic sound.

So here comes my question: does anyone have any suggestion on how to deal with that? I have no experience at all with quad sound… and I can’t find any related post here (or suitable C++ library on the interwebs, for that matter).

One of the project’s modules will be outputting MIDI, so we can consume MIDI from, say, Reaktor, and generate the sound from there, but -again- I’d love to do it with OF (and will definitely be the best for the students…)

So, any comment, help or suggestion is more than welcome!

Thanks a bunch, and best wishes to everyone!
–k

openFrameworks sound output uses a library called Fmod. have a look around their website, you might find some more info there…

otherwise, have you considered doing the sound output through different software? whenever i’m doing sound in a project, that is even slightly more complex than just triggering samples, i use [url=http]Pure Data[/a] and communicate with it via Open Sound Control.

to add on to what damian said – OF uses two sound libraries / approaches internally:

a) fmod for playing samples and streaming audio
b) rtAudio for real time callback based audio / synthesis and analysis

both could be setup for 4 channels. Right now, the rtAudio is kicked off with the number of input and output channels, and this could easily be four if the sound card can handle it. at the same time, rtAudio’s pretty low level, and it might not be what you are looking for (you either have to synthesize the sound yourself, or tap into other libraries). Fmod would take some minor hacking, but it could work with four channels (there is 3d audio support, listeners and positioning, etc). you can poke around the fmodex forum and ask if they have code examples.

take care!
zach

Hi guys.

Thank you for our answers…

@damian) Yeah, I’ve been thinking about the PD (+OSC) approach… but I am hoping to help the workshop participants to solve the problem with oF.

I’ll start looking into Fmod right now.

I know that in many cases (if not all) half of the problem is finding the right tool, but if the participants get the feeling that (almost) anything can be done if you program it, I’d be very happy :slight_smile:

@zach) thanks!

tom

When you download and install the fmod libraries you’ll get a bunch of samples installed. On OSX they go into Developer/FMOD API/examples (not sure where they go on Windows). Take a look at the multispeakeroutput and multiplesoundcard examples. Both those will show you how to get going with multispeaker output. Have fun :slight_smile:

Thanks!

I’ve just found this (very basic) tutorial. I’m copying the link here just in case someone else is also as clueless as I was yesterday :smiley:

http://jerome.jouvie.free.fr/Fmod/Tutor-…-rial03.php

tom