[Linux-Biella] DOMANDA: pulseaudio pulsa

[Roberto Zanetto]

Paolo Ciarrocchi wrote:
> On 11/3/08, Roberto Zanetto <zanetto a iol.it> wrote:
>   
>> Ho parecchi problemi con Pulseaudio su FC9. E' possibile sostituirlo con
>> qualche altro porgramma?
>> Soprattutto come si fa a disinstallarlo?
>> In quanto quando ho cercato di disinstallare evolution con yum (yumex o
>> packagekit) sono stati disinstallati molti pacchetti di gnome che ne
>> hanno pregiudicato il funzionamento.
>> Ho cercato con google ma non trovo una procedura che vada per fedora,
>> molti suggerimenti riguardanti ubuntu ma diversi fra loro: si vede che
>> chi utilizza fedora e' masochista e preferisce giochicchiare con questo
>> sarchiapone.
>> Grazie dell'attenzione
>>     
>
>
> pulsaudio è il futuro. Invece che cercare di capire come
> disinstallarlo perché non:
> - ci spieghi in modo chiaro e dettagliato i tuoi problemi
> - segnali i problemi a fedora e invii qui in lista gli identificativi
> dei bug report?
>
> ciao,
>   
Sull'utilita' di pulseaudio ho trovato questo:

To explain why, let's first take a look at the advantages which 
PulseAudio claims to offer:

    * /Sound mixing: different applications can produce sound at the
      same time without any problem./ I have been using Alsa for years
      now, either with sound cards which support hardware mixing, either
      with Alsa's dmix software mixing. I've never had trouble playing
      different audio streams at the same time with this set up.
    * /Moving sound streams between different audio cards./ I only have
      one sound device, so I do not need this feature. This feature
      could be handy for people using headsets for VoIP application,
      because they can move their VoIP application to the head set, and
      keep their music player on the normal sound card. I am not sure a
      sound server is really needed for that: I would expect VoIP
      applications to have a configuration panel where the user can
      change the audio device to use.
    * /PulseAudio makes it possible to set different volume levels for
      all applications./ Most applications today already use their own
      internal volume mixer like for example Rhythmbox, Amarok, Totem,
      Kaffeine, Pidgin,... Because of that, I have never felt the need
      to use this PulseAduio PulseAudio feature during these months, and
      I doubt even lots of users will know of the existence of this
      possibility.
    * /PulseAudio does higher quality resampling than Alsa for sound
      cards supporting only 48Khz output./ I have such a sound card, and
      did some listening tests with headphones. I could clearly hear a
      difference between PulseAudio's low-quality "trivial" resampler
      and its better "speex-float-1 resampler", however I could not hear
      a difference between PulseAudio's higher quaility "speex-float-3"
      resampler and Alsa's resampler: both sounded good to my ears. I
      did not really find any reliable listening tests proving that
      Alsa's resampler is bad, only some vague claims.
    * /PulseAudio makes it possible to send sound over the network to
      another machine running PulseAudio./ Without any doubt, this is a
      great feature for thin clients, but this feature is only used
      extremely rarely on normal desktop systems.

So I did not find any advantage in using PulseAudio. Still, the 
potential features could be interesting and make it worthwhile to keep 
PulseAudio nevertheless, one never knows these features might become 
useful one day? No. For me there were too important disadvantages when 
using PulseAudio:

    * /PulseAudio's resampler uses a lot of CPU time./ (Mandriva bug
      #36084 <http://qa.mandriva.com/show_bug.cgi?id=36084>). On my not
      too slow Athlon 64 3500+ CPU, PulseAudio was using more than 7 %
      of CPU time when playing music with the default resampler.
      Choosing the lower quality resampler speex-float-3 made it use
      still more than 3 %, which is still a lot on such a CPU. Rhythmbox
      itself also seemed to use more CPU time when using PulseAudio than
      when using Alsa. There is clearly a lot of optimization to do
      here. The only reaction by PulseAudio's developer is that
      MMX/SSE/SSE2 optimization patches are welcome...
    * /PulseAudio forces every application to use PulseAudio./ When
      PulseAudio is activated, other applications cannot access the
      sound device directly. Alsa applications are routed through
      PulseAudio with a libalsa plug-in, OSS applications with the padsp
      wrapper. As the libao bug
      <http://qa.mandriva.com/show_bug.cgi?id=36965> shows, this is
      still not working like it should. Even KDE's Arts sound server
      output is routed now through the PulseAudio server: that means KDE
      3 users will enjoy running two sound servers at the same time! Not
      only are there still difficult to debug interaction problems
      <http://archives.mandrivalinux.com/cooker/2008-01/msg00498.php>
      (known by Fedora for months
      <https://bugzilla.redhat.com/show_bug.cgi?id=361891>, but
      unresolved), but it seems clear to me that this has to introduce
      extra latency for audio applications. In the Windows world, there
      are different professional studio applications which require very
      specific sound hardware. How could such applications benefit from
      minimum latencies and other advantages of these hardware, if they
      cannot access it directly, but have to pass through PulseAudio?
    * /PulseAudio stops all sound if you switch to another console
      and/or switch to a different user./ If I switch from X to tty0,
      there is no reason why PulseAudio should mute all my audio
      applications. In the end it feels like PulseAudio prohibits me to
      use tty0 and thinks that I should use an X terminal instead. I
      don't like being forced to change my behaviour. If I want to stop
      my music, I will really do so myself, there's no need to decide
      this for me.

Non mi sembra che pulseaudio faccia cose che mi siano utili. Mi sembra 
la stessa situazione di network manager: niente di utile, solo problemi 
con la rete, da quando mi hanno consigliato e detto come toglierlo vado 
bene.
Ho parecchi problemi con pulseaudio dovuti al fatto che per far 
funzionare skype ho dovuto fare tutta una serie di impostazioni le quali 
pero' danno inconvenienti come ad esempio utilizzare mic boost genera 
ritorno in cuffia e poi tali impostazioni fanno andare male l'audio con 
ekiga che uso per un account voip

-------------- parte successiva --------------
Un allegato HTML è stato rimosso...
URL: http://ml.bilug.linux.it/pipermail/linux/attachments/20081103/779b59fe/attachment.html