Announcement

Collapse
No announcement yet.

PulseAudio 2.0 Is Set To Be Released Very Soon

Collapse
X
  • Filter
  • Time
  • Show
Clear All
new posts

  • #61
    Few things to point out.

    1. Audio card that takes a power tail from the power supply like a video card. Asus Xonar Essence STX (I have one and it is great but it needs extra power to run the built in headphone amps).

    2. I want bit perfect audio but Pulse can't do it that I am aware. I am curious to see the new sample rates it see if the sound quality improves.

    3. Right now if you want bit perfect audio, get deadbeef. Set the sound settings to use the ALSA driver and bypass pulse or any other mixing software. Stream the digial out to your expencive speakers. Because deadbeef is taking over the sound you can't play any other sounds, but if you are really trying to listen to your 24bit 96Khz or 192Khz songs you are not going to be wanting any other sounds in there.

    For those that try and quote what humans can hear and how it doesn't make any difference I can hear it. From CD to 96Khz. Though I will say that it could be the extra bits more than the frequency. I have some 24bit 48Khz songs that sound better than CD. Most people who I have done a back to back sound test with, can tell the difference. Personally I can't hear the difference between 96Khz and 192Khz though. I have some of the same recordings at different frequencies and even as MP3s at the highest settings. It does make a difference. I should mention I have B&W 704 speakers with the rest of the sound system to match. My high quality music is all recorded in flac and are high resolution from the studio (www.HDtracks.com), not upsampled from a 16bit 44Khz song. I also sit in the sweet spot and listen to music doing nothing else, no playing games, no fiddeling with things, just sitting and totally imersed in the music. If I could get a pass through setting with no mixing and no buffering in PA that would make me happy.

    For my everyday stuff, playing games and watching youtube videos and whatnot, Pulse seems to work great for me.

    Comment


    • #62
      Originally posted by allquixotic View Post
      Actually, it's probably not. In the general purpose computing market (laptops + desktops + tablets + home movie devices), the two chip designs that basically dominate the market are chips based on Intel's HD Audio standard (5.1 or 7.1 channels, integrated on motherboard, software mixing, blah blah); and chips based on the HDMI Audio standard (similar support as HD Audio, but supplied as a companion ASIC on a SoC or discrete graphics card). Both of these only do software mixing.

      If you go a little older, AC'97 was the dominant chip standard, and that also only supports software mixing.

      If you go portable (for people who hate their on-board sound or don't have on-board sound), USB Audio Class 1.0 (requires USB 2.0) is the dominant standard, and that also only supports software mixing.

      What, do you suppose, is the combined percentage of market share between HD Audio, HDMI Audio, AC'97 and USB Audio Class 1.0, compared to other chips which do not fall into any of these categories (and discounting software-mixing DSP chips embedded in small cellphone/smartphone ASICs)?

      I think 99% would be a gross understatement; you need to add a few .999's to it to reach a semblance of precision.

      So yes, you are extremely rare. Phoronix membership tends not to be representative of the general populace. This site is for enthusiasts. The fact that three or four people have chimed in saying they have hardware mixing just goes to prove my point.

      Funny thing is, I know a lot of audiophiles personally who are perfectly happy with their consumer-grade HD Audio or HDMI Audio solution. To them, like many of us, it's the quality of the headphones you use that makes more of a difference in audio quality, not the quality of the DSP or whether the DSP offloads mixing work from the CPU. Even consumer-grade DACs are incredibly powerful these days, so unless you are using your audio hardware to actually produce content that will generate extreme amounts of revenue and/or publicity, or unless you just have spare money sitting around, I can't see any reason to buy a discrete audio card that does hardware mixing. Just the thought of an audio card -- something you couldn't live without in the 90s -- seems amusing to me now, just by reading the words "a-u-d-i-o c-a-r-d". It's like reading the words "math coprocessor". Well of COURSE everyone's CPU has a math coprocessor, dummy! What do you think this is, 1978?! Yeah. That's how I feel about audio cards.

      One other thing that has me genuinely interested: people claim that not having PA running saves them RAM or CPU time. Well that's just dandy, but something, somewhere, is still mixing your audio. How power-efficient is that chip? How many streams can it handle at once? Does it buckle under sustained load? If it has a bug, do you have the expertise to upload new firmware to it (assuming it's possible to do so at all)?

      I haven't been keeping up with the fringes of audio technology lately, but my gut feeling is that audio card manufacturers aren't exactly using 22 nm technology for their boards. And it's pretty clear from Intel's recent innovations that smaller (and smarter; see Ivy Bridge's on-chip voltage regulator) makes a chip more power efficient. Unless you've physically measured the voltage consumed by your audio card's HW mixing and found it to be lower than an optimized CPU-based solution such as PulseAudio, I'm going to wager that doing it on the CPU will eat less power.

      But, then again, if I actually had a pro audio card with hardware mixing, I'd probably want to use it -- to be fair. Especially if I have a desktop and power consumption isn't really a factor, when you consider that audio cards aren't eating up power nearly as much as video cards do; I've never heard of an audio card that takes external PCI-E power plugs like the big Radeons and GeForces do.

      People have expressed interest in using PA's protocol features, plugins and routing features with hardware mixing before, but it seems like it'd be a fairly difficult task. I'm sure it's possible for certain classes of hardware, but you would end up having to develop a hardware interface layer that's closer to a general purpose computer, or at least provide some mechanism for PA to modify buffers already queued up on the card, and read back existing buffers, kinda like what the more recent OpenGL specs have provided for GPUs. You'd basically end up having an audio accelerator card with very similar "programmable fixed-function" features, analogous to what you saw on GPUs about 7 or 10 years ago, before they became fully programmable. Because if you're going to make it fully programmable, you might as well just do it on the CPU, or -- hell -- even the GPU.

      Audio on the GPU. Now you have me genuinely interested.

      OpenCL "hardware mixing" in PulseAudio. hahahahahahahahahahahahahahahahahaha. Is it even possible? I'm just thinking aloud here.
      Allquixotic,

      You're sharp reasoning prompted me to try pulseaudio again. I removed my dmix asound.rc and reinstalled alsa then installed pulseaudio. I'm sorry to report, but pulseaudio still crackles loudly and consistently on both of my machines. I'm going to stick to dmix for another year or so before I try again.

      Comment


      • #63
        WOW. I really should proofread. Let me try again below.

        Your sharp reasoning prompted me to try pulseaudio again. I removed my dmix asound.conf, reinstalled alsa, and then installed pulseaudio. I'm sorry to report, but pulseaudio still crackles loudly and consistently on both of my machines. I'm going to stick to dmix for another year or so before I try again.

        Comment


        • #64
          Originally posted by frie2 View Post
          WOW. I really should proofread. Let me try again below.

          Your sharp reasoning prompted me to try pulseaudio again. I removed my dmix asound.conf, reinstalled alsa, and then installed pulseaudio. I'm sorry to report, but pulseaudio still crackles loudly and consistently on both of my machines. I'm going to stick to dmix for another year or so before I try again.
          Hi,

          "crackles loudly" is not going to help anyone resolve the problem. Chances are that so few people use your sound hardware that you might be the only one who would care to report the issue. Once it's reported, it can probably be fixed.

          Most likely this is not pulseaudio's fault, but your ALSA drivers. One downside of using pulseaudio is that crappy audio drivers that don't properly implement the full ALSA API are simply not acceptable anymore. So it's been a HUGE wakeup call for the ALSA developers to have to support pulseaudio on all kinds of hardware, and as a result, the quality of all the audio drivers -- whether using PA or not -- has improved drastically since PA started pushing that angle.

          Don't believe me? Check out all the patches contributed to ALSA by PulseAudio developers, or patches suggested at a high level by a PulseAudio developer, then developed by an ALSA maintainer in response. 2007 - 2010 saw a tremendous amount of work along these lines.

          Chances are, if you try again in a year without taking any action, nothing is going to be better. So report the problem! PulseAudio has a mailing list. They're very responsive. Be prepared to provide your alsa-info.sh results: http://git.alsa-project.org/?p=alsa-...s/alsa-info.sh

          You don't happen to have a Creative X-Fi, do you?

          Comment


          • #65
            I don't think my hardware is all that rare. And no, I don't have an X-fi. I wouldn't touch creative with 10ly pole.

            http://www.alsa-project.org/db/?f=9b...c147cf475deeb9

            Comment


            • #66
              Originally posted by frie2 View Post
              I don't think my hardware is all that rare. And no, I don't have an X-fi. I wouldn't touch creative with 10ly pole.

              http://www.alsa-project.org/db/?f=9b...c147cf475deeb9
              Which of your sound cards are you using that crackles? The HDMI audio on the Radeon, or the Azalia codec on the motherboard?

              Comment


              • #67
                The Azalia. I've never tried the hdmi audio actually.

                Comment


                • #68
                  Originally posted by DanL View Post
                  I can easily hear the difference between my M-Audio Revo and my onboard ALC892 using the same headphones. The M-Audio cost < $70 when I bought it 7 years ago and it was worth every penny.


                  Funny thing is, I know a lot of people that like to think of themselves as audiophiles with music collections full of 128kb mp3's...

                  Right on, dude. I used to have a Revo 5.1 but wanted to experiment with Pulseaudio more and the Revo would only work with the timer-based scheduling off so I replaced it with an HT Omega Claro Halo. The Revo with Klipsh ProMedia Ultra 5.1 were unbelievable, certainly better than any other computer I had heard before. I've slowly moved to replace all my music to flac.

                  Comment


                  • #69
                    Pro-audio perspective on pulseaudio

                    Pulseaudio (comments based on current version on Fedora 16 - 0.9.23)

                    The good:
                    • Wakeup based audio mixing platform to linux desktop. Major benefits for power saving / CPU and unifying a lot of the mess that was Linux audio servers.
                    • Dynamic audio device plugging done correctly
                    • Userland tools - finally some GUI tools in "User head space" that are natural
                    • Forcing the ALSA drivers to correctly report buffer fill levels for timing


                    The bad:
                    • Yet another linux sound server... (although with it's adoption, it's rapidly becoming the server of choice). The XKCD strip about "standards" springs to mind.
                    • Doesn't solve any pro-audio use-cases (and the pulseaudio guys acknowledge this). It's not pulseaudio's remit to compete with jack, but it does illustrate that maybe the solution isn't quite there...
                    • When a new stream is opened with different latency requirements, an audible pop is heard in the output stream as pulseaudio adjusts it's buffers and wakeup timing. It may just be the app / protocol (minecraft, alsa) that causes this. I should investigate a little further but time... is fleeting...
                    • Introducing a new "plugin" format. To do any stream processing (echo cancellation / reverb etc) pulseaudio should be using existing plugin standards (LADSPA/LV2)


                    Coming in V2:
                    • Virtual sound sink / Effects - this one is telling for me, and smells a bit like Pulseaudio is starting to go down the route of being a sound graph (with effects and other bits too). This is starting to encroach on Jack territory...


                    So what's my real opinion?

                    Well don't get me wrong, I think we're going in the right direction with Pulseaudio, I just can't escape the feeling that it does about 80% (value pulled from ass) of needed audio requirements, whilst punting on some things it could do.

                    In my ideal world, pulseaudio would be _the_ sound server and audio graph host for the linux desktop (ala apple's audio units and core-audio). We could then finally move on from having multiple tools and servers for all this stuff and focus on this one engine to rule them all.

                    Jack itself has certain issues - e.g. only one global namespace for connections, no nesting of graphs, no adaptive latency control, applications don't run their audio units inside the server process (which would take us to latency perfection).

                    I'm wishing I know, and a lot of my gripes stem from a pro-audio perspective - but some of the normal real world applications have similar requirements to pro-audio (think rhythm games, adding desktop wide reverb / eq ).

                    Cheers

                    Comment


                    • #70
                      Originally posted by silenceoftheass View Post
                      • When a new stream is opened with different latency requirements, an audible pop is heard in the output stream as pulseaudio adjusts it's buffers and wakeup timing. It may just be the app / protocol (minecraft, alsa) that causes this. I should investigate a little further but time... is fleeting...
                      Not that it excuses PulseAudio but on Gentoo, my Minecraft package builds the dependencies from source and as such, OpenAL will use PulseAudio directly if you wish. I have definitely not heard any pops.

                      Comment


                      • #71
                        Originally posted by Chewi View Post
                        Not that it excuses PulseAudio but on Gentoo, my Minecraft package builds the dependencies from source and as such, OpenAL will use PulseAudio directly if you wish. I have definitely not heard any pops.
                        Same here. In fact, the only time I've ever had the problem was with Skype. And that's likely more due to Skype than pulse.

                        Comment

                        Working...
                        X