Mixing audio

Reply to Mixing audio on Sun, 27 Jan 2013 13:53:10 GMT

pouk — Sun, 27 Jan 2013 13:53:10 GMT

hello everybody,

i made this very simple patch in order to mix several audio signal. each audio signal
is summed to his closest neighbor. so obviously when i decrease the volume of one source, it decrease the general volume of the output. how can i avoid that ?
so i would like to adjust the volume of each audio signal without deacreasing the general output. even if one track or more are at zero the master would be at a fixed full volume.

thanks

http://www.pdpatchrepo.info/hurleur/mixing.pd

Reply to Mixing audio on Mon, 28 Jan 2013 20:38:11 GMT

pouk — Mon, 28 Jan 2013 20:38:11 GMT

nobody ?

Reply to Mixing audio on Mon, 28 Jan 2013 22:06:43 GMT

austin_ep — Mon, 28 Jan 2013 22:06:43 GMT

Are you wanting to maintain say, a constant value of -12dB no matter how many signal sources you have? Or do you just want the output to always be on at a pecified volume? For the later option I would personally just use

[Outbound Audio]
|
| [knob] (Set from 0 to 1)
| /
[*~]
|
[dac~]

However, if you want something along the lines of what I first described, I haven't a clue how to do that, I am sorry! I'm new here myself.

Reply to Mixing audio on Tue, 29 Jan 2013 12:22:22 GMT

pouk — Tue, 29 Jan 2013 12:22:22 GMT

yes i am more interested by what you first described. i would like to maintain the volume at a certain db value for the master and so whatever the volume of each track.
thanks for your interest !

Reply to Mixing audio on Tue, 29 Jan 2013 15:04:30 GMT

mnb — Tue, 29 Jan 2013 15:04:30 GMT

if you have signals with a constant amplitude (like the oscs in your example),
you can multiply the output with the reciprocal of the sum of the input levels. (if all 4 inputs are 1, it is 0.25 for example). otherwise (for more complex signals) you could build something like a compressor.

Reply to Mixing audio on Tue, 29 Jan 2013 15:59:55 GMT

baptiste_c — Tue, 29 Jan 2013 15:59:55 GMT

Just for fun, a cake = f(hunger) mixer
Not scalable (yet)

Edit : oops, little mistake : the first moved fader started at full volume, i uploaded a better version.

eaten_cake = f(how_many_people, hunger)

http://www.pdpatchrepo.info/hurleur/relative_mixing.zip

Reply to Mixing audio on Tue, 29 Jan 2013 18:35:16 GMT

austin_ep — Tue, 29 Jan 2013 18:35:16 GMT

That is a really cool, and admittedly cleverly themed little patch dwan! Thank you for posting it up for us. It is always so helpful to see the sort of 'behind the scenes' in a patch of which I had an idea for. I know that pouk started the thread, but I was quite interested too.

Reply to Mixing audio on Tue, 29 Jan 2013 18:50:47 GMT

baptiste_c — Tue, 29 Jan 2013 18:50:47 GMT

Thanks ! That was fun to do. How curious, i stumbled upon this today just before reading this thread : http://www.vttoth.com/CMS/index.php/technical-notes/68

Reply to Mixing audio on Tue, 29 Jan 2013 19:27:55 GMT

pouk — Tue, 29 Jan 2013 19:27:55 GMT

thank you for this patch it's exactly what i'm looking for !
it works perfectly ! now i have to study it.

great