hi all,

i've made a pre-recorded 8-channel sound installation for an exhibition in an art gallery. i sequenced it on protools in a friend's studio, but now i need to find a way to play it back in the gallery using PD on my computer (which doesn't have protools...). i know there are easier ways to do this, but i don't own any sequencing software myself!

i also would like the playback to start automatically, so that all i need to tell the gallery staff to do is turn on the computer (i suspect not all the staff are 100% computer literate).

is anyone able to help me with this? my 2 issues are:

1. the sound is saved on my hard disc as 8 .wav files of exactly the same length (about 1 hour duration). i need to play them simultaneously on a continuous loop through my multichannel sound card. would [readsf~] be the best choice? i think there's too much data to play from RAM. are there any example patches out there that i could modify for an 8-channel environment?

2. having my patch start automatically and begin playing the sound files when the computer is turned on. i have no idea how to do this... my computer runs windows vista (blergh!). anyone??

thanks!

jon.

i think readsf~ would work fine. the right outlet gives a bang when the file has finished playing, so you'd just hook up one of those right outlets to trigger the files playing again. I don't think you'd get any trouble with sync, as long as your computer is fast enough to playback 8 files without glitching.

also, you can set pd to run a patch automatically on pd's startup. i can't remember exactly how to do it, but i reckon a search through this forum and the pd mailing list archives will find the answer. make sure also that you do a [loadbang -> ;pd dsp 1] inside the patch to turn on 'compute audio'.

then, it would just be a case of fiddling round with your windows startup preferences to make pd load on startup.

Also as far as using multiple outputs [dac~ 1 2 3 4 5 6 7 8] will do the trick so long as you have an 8 output soundcard.

2. in xp there is a autostart folder where you just drop your patch in.
start->programs->autostart
might be the same in vista, or otherwise might be that vista is crap
if it succeeds in opening, then use loadbang in the patch to make it play automatically

thanks for the help everyone!

in case there's any other newbies like myself out there trying to do the same thing, i managed to get this working using eight [readsf~] objects, one for each channel.
in order to ensure the channels don't get out of sync somehow (because the installation might be playing for a very long time) i took the bang output of each [readsf~] and put if into a counter, which starts playback again when it has recieved 8 bangs.
i'll posts my patch here when i get home again.

to make the patch load and play when the computer starts up, i made a .bat file containing a command line script which runs PD, opens my patch, selects my multichannel soundcard, and sets the number of output channels to 8. this page was very useful for learning how to use the PD command line:

http://en.flossmanuals.net/PureData/AdvancedConfig

in vista, all you need to do is put the .bat file in the "startup" folder (open this by going to startmenu->all programs->right click on startup and choose 'open') and it will run the batch file when the computer starts up.

i've also installed windows steady state (http://www.microsoft.com/downloads/details.aspx?FamilyID=d077a52d-93e9-4b02-bd95-9d770ccdb431&displaylang=en) which let me create a user account for the gallery that only allows access to PD and the files for the installation, which are in their own partition on the hard disc. everything else is blocked, so gallery staff can't accidentally change the sound configuration etc.

brilliant! glad it all worked out.

here's the patch i used.

note that it's 7 channels, not 8 like i originally said. you'll need to change the value in the [moses] object to match the number of channels you use. and you'll also need to set the correct path in the [readsf~] objects to match the location of your sound files.

sorry it's a bit messy... haven't got time to clean it up yet!

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

...and here's the .bat file i used to make the patch load up and start playing when the computer turns on. i put this in the startup folder (see post above). if you use it, you'll probably need to change the values of the 'audioindev' variable etc to select your soundcard. also make sure you set the number of channels to match however many you use. the website i posted a link to previously tell you how to do all this.

oh, and remove the .txt extension from the file!

x jon

http://www.pdpatchrepo.info/hurleur/voice.bat.txt

Hi Jon,

I'm trying to do something incredibly similar with Pd - I also have a sound installation with 8 speakers which I want to control via a patch.

In my installation I have lots of little snippets of sound which I want to play one after the other, so that the sound 'jumps' across speakers in a pre-planned order - do you have any idea how I could adapt your patch to do this?

I'm having a similar issue as well, in that I would like other students/staff to be able to run the installation without having to open pure data and activate a bang or something similar. I don't quite understand how your file works - what exactly would I need to do in order to have pure data open and my sound files to start playing? I'm not sure what version of windows I'll be working with as a friend is lending me a computer for my sound piece.

Thanks for any help and advice you can give!