[PD] pd in ubuntu 8.04: pd hijacks alsa?

[Lewis Pike]

IOhannes m zmoelnig <zmoelnig at iem.at> writes:

> On 2010-12-05 22:34, Aaron L. wrote:
>> This is somewhat of a complete newb issue so I apologize up front for
>> that.......
>> 
>> However, it seems that I cannot use pdextended and watch a youtube video at
>> the same time (the youtube vid is a pd tutorial).
>> 
>> Here's what it's starting with:
>> 
>>  pasuspender -- /usr/bin/pdextended -alsa %F
>> 
>> Is it absolutely necessary to start pd with 'pasuspender'?
>> 
>> When I don't (i.e. start it like this:  '/usr/bin/pdextended -alsa' ), I get
>> a bunch of 'device or resource busy' messages in the terminal and I don't
>> get any audio when doing the whold testtone thing).
>> 
>> Is there any way around this?
>
>
> well, this is exactly the way how alsa is supposed to work:
> - only one application can access a (hardware) device at any point
>
> pulseaudio is a way to circumvent this limitation.
> running Pd in pasuspender, effectively disables pulseaudio including all
> it's features.
>
>
> luckily there are ways around that.
>
> - use pulseaudio (not a good option, as Pd currently doesn't support it
> :-(; btw, pa is geared towards the ordinary consumer multimedia desktop
> where people would like to watch their youtube videos and at the same
> time listen to the latest p!nk smash hit; Pd is not really targeted
> towards that marketm, hence pa is not done yet)
>
> - use alsa's "dmix" interface; "dmix" is a virtual device that allows
> several applications to send their audio output to the same hardware
> device (without the applications even knowing of it). i'm not 100% sure
> whether you can actually access this from within Pd....
>
> - use "jack". now you can think of jack as "pulseaudio for pros", it
> allows to route the output of one process to the input of another
> process (or more); "process" can be both hardware (your soundcard) or
> software (Pd, your browser,...).
> there are also ways to make alsa-only applications (e.g. your browser)
> use a pseudo alsa device that really sends all audio to jack (thus the
> application need not be aware of jack at all)
>
>
> madt
> IOhannes

I'm new to Pd as well and ran into the ver same problem.  After a bit of
guesswork, I tried running Pd with the command:

pd -alsa -alsaadd dmix

which seems to add an unlabelled audio output in the Pd alsa
configuration menu.  When this output is selected, it solves the
problem.  I works well enough, but I haven't tried using jack.  Can
anyone who has used both dmix and jack offer offer an opinion on the
pros and cons of each?

.Lewis