ALSA: Audio Compression Offloading, Power Savings

[phoronix]

Phoronix: ALSA: Audio Compression Offloading, Power Savings

Besides lots of graphics talks at the GStreamer 2012 Conference, the Advanced Linux Sound Architecture (ALSA) was talked about with a status report and mentions of some features soon to be landing in future Linux kernel releases...

http://www.phoronix.com/vr.php?view=MTE3MTQ

[uid313]

Does?

Does PulseAudio do bit-perfect playback?
How do I do I set it up to do so?

Does PulseAudio support THX, Dolby, DTS, SRS, DLNA, surround, virtual surround, etc and all those fancy logos on audio equipment which I have no idea what they mean?

Does PulseAudio support playing music at different volume on different speakers, and different songs (output streams) to different speakers in different rooms like Sonos multi-room music system?

[bluestealth]

Does PulseAudio do bit-perfect playback?
How do I do I set it up to do so?

Does PulseAudio support THX, Dolby, DTS, SRS, DLNA, surround, virtual surround, etc and all those fancy logos on audio equipment which I have no idea what they mean?

Does PulseAudio support playing music at different volume on different speakers, and different songs (output streams) to different speakers in different rooms like Sonos multi-room music system?

Who are you talking to?

[jrch2k8]

Does PulseAudio do bit-perfect playback?
How do I do I set it up to do so?

Does PulseAudio support THX, Dolby, DTS, SRS, DLNA, surround, virtual surround, etc and all those fancy logos on audio equipment which I have no idea what they mean?

Does PulseAudio support playing music at different volume on different speakers, and different songs (output streams) to different speakers in different rooms like Sonos multi-room music system?

those are good questions but im not really sure, we need an audio guru

[uid313]

Who are you talking to?

Nobody in particular.
I was just asking the questions plain out so anyone who knows can feel free to answer.

[schmidtbag]

Does PulseAudio do bit-perfect playback?
How do I do I set it up to do so?

Does PulseAudio support THX, Dolby, DTS, SRS, DLNA, surround, virtual surround, etc and all those fancy logos on audio equipment which I have no idea what they mean?

Does PulseAudio support playing music at different volume on different speakers, and different songs (output streams) to different speakers in different rooms like Sonos multi-room music system?

As for half of those logos you mentioned, they're either just company names or aren't directly relevant to your sound card. ALSA does support surround sound, but my #1 gripe about ALSA is it's a royal pain in the ass to get surround sound and channel redicting working properly. No matter what guide I follow, something goes wrong. They're not that hard to follow, they just don't work. This is mostly because the way you configure .asoundrc files gets outdated and nobody updates their tutorials. If you want a quick easy way to mux multiple channels, go with PA, it does a pretty good job at that IMO and is the only compelling reason to use PA over ALSA. Even if setting up surround sound in ALSA worked as advertised, PA's CLI methods for setting up surround sound are still easier.

I'm currently an ALSA user and pretty much always have been. I do have surround sound but I rarely ever need it in linux so I don't care so much that it doesn't work for me.

Ranting aside, playing music at different volumes on different speakers is generally achieved by a sound server like PA, but you could also just run 2 instances of a program and tell each to redirect the sound to w/e speakers you want it to play on. Pretty much the point of ALSA is to just get your hardware functioning. You use a sound server to do the fancy stuff.

[ShadowBane]

Does PulseAudio do bit-perfect playback?
How do I do I set it up to do so?

Does PulseAudio support THX

THX is a brand.

Dolby

also a brand

DTS

AFAIK: Yes, you can do DTS passthrough.

SRS

You mean the audio processing stuff that makes your music sound terrible? No, but it is often done on the stereo receiver anyway.

DLNA

There is no reason a sound server would even consider supporting DLNA. If you want to access a DLNA server use XBMC.

surround

Yes, PA can do more than 2 channels.

virtual surround

Yes, it can also upmix to more than 2 channels.

etc and all those fancy logos on audio equipment which I have no idea what they mean?

If you don't know what they are why do you care. Also, most of those are only needed by the thing that has the stickers on them.

Does PulseAudio support playing music at different volume on different speakers, and different songs (output streams) to different speakers in different rooms like Sonos multi-room music system?

Actually, yes. There is a guide on the Arch wiki on how to seperate the headphone jack on the front of the computer from the speaker jack on the back so that you can move streams between them and put different stuff on them. Quite convenient.


Also, this thread is about ALSA, why are you asking about PA features?

[liam]

Phoronix: ALSA: Audio Compression Offloading, Power Savings

Besides lots of graphics talks at the GStreamer 2012 Conference, the Advanced Linux Sound Architecture (ALSA) was talked about with a status report and mentions of some features soon to be landing in future Linux kernel releases...

http://www.phoronix.com/vr.php?view=MTE3MTQ

Hmm, if these things happen it duplicates it good bit of the things PA does (wall timestamps, output redirection (just jack for the time being, but that was, and in particular, one of the advantages PA brought)). I wonder if this includes that pll/dll work that was mentioned in another thread(admittedly that is driver, and rather than ALSA, specific).

[thofke]

Does PulseAudio do bit-perfect playback?

I believe PA resamples everything to a predefined samplerate (see /etc/pulse/daemon.conf), so if your source material does not have the same samplerate, it is by design not bit-perfect.

[uid313]

I believe PA resamples everything to a predefined samplerate (see /etc/pulse/daemon.conf), so if your source material does not have the same samplerate, it is by design not bit-perfect.

The SoundBlaster Live! resampled everything internally to 48 kHz.
People were pissed.

Now when PulseAudio does it, its okay?