[PD] more than 2 dac/adc's

[pdlist at jlndrr.net]

Hi,

> we did a sound
> installation using 4 crappy consumer soundcards all controlled by one 
> pd
> process, and it worked

Do you think it's possible on OS X 10.3?

With the packaged installer for OS X, as I posted earlier I couldn't 
even use a different number of ADC and DAC channels (Apparently a 
portaudio limitation, reported a list member) I used Soundflower 
virtual sound card as a trick.

So if you can share you experience, I will be delighted

I first had two separate goals:

1- Use my 6 channels sound card when I have only 2 channels input. This 
one is fixed by the use of Sound Flower.

2- Use a lot of cheap USB sound card for mic INPUT, say 10 * 2 Inputs. 
I suppose clock will not be a problem for Inputs? But I can't see how 
to do this one...

Thanks all,
jln

>
> IOhannes m zmoelnig wrote:
>
> just to reiterate this for the archives with an anecdote: we did a 
> sound
> installation using 4 crappy consumer soundcards all controlled by one 
> pd
> process, and it worked, but the slight differences in each cards time
> sync meant that there were noticable clicks'n'pops and grinding sounds
> from the cards different cards.  its a good way to do something for fun
> on the cheap, but *not* hifi in any way.
>
>> this depends.
>> pd can not handle multiple soundcards that provide their own
>> reference-clock to get the sampling-rate. if you have two (say)
>> soundblaster-cards, chances are very low that their clocks will be
>> exactly the same, e.g. one card will be clocked at 44100Hz and the
>> other at 44098Hz. the 2 cards will get out of sync and after some time
>> you will get a dac-slip on one of your outputs.
>>
>> however, some cards can be synced - either by slaving them to
>> wordclock or some digital audio signal (if they have digital I/O) or
>> via some special onboard sync-cable (RMEhammerfall-cards have this
>> feature so you can stack 2 cards)
>>
>> how else am i supposed to get 48 channels out of my computer (in times
>> prior to MADI) ?
>>
> --