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- To: proaudio@xxxxxxxxxxxxxxxxxxx
- Subject: Re: [proaudio] Real-Time for audio playback?
- From: Grant <emailgrant@xxxxxxxxx>
- Date: Mon, 28 Dec 2009 11:09:42 -0800
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>> I'm looking for ways to improve the digital audio playback on my
>> Gentoo system. I'm bypassing dmix by sending audio output straight to
>> my USB DAC by specifying "plughw:0,0" in mpd.conf. Would the
>> Real-Time kernel be beneficial? I've heard there are ALSA latency
>> tweaks that can be made as well?
>>
>> - Grant
>
> Is there a reason that you need lower/known latency in your audio
> path? I.e. - is it important that there's 2.4mS from when it comes of
> the hard drive until it becomes audio?
>
> Most people here are using the jack-audio-connection-kit and
> jack-enabled audio apps to create something approaching the way a
> studio controls its audio path.. This allows multiple audio apps all
> the gain access to the sound card in a latency controlled manner.
>
> I don't know what dmix actually is. I don't use it myself. Maybe
> someone else can comment on that. If it's some automagic way of mixing
> sound from different apps then getting rid of it is (IMO only) a good
> idea in terms of sound quality.
>
> What rt-sources does for you is allows you to get your latency much
> lower than vanilla-source/gentoo-sources. (I.e. - off disk and out to
> the speakers faster) It doesn't change the sound of anything. Using
> Jack will allow you to see how you're doing with your hardware.
>
> Hope this helps. Feel free to ask questions. I know you're new to this
> topic. This is a friendly list where folks aren't expected to know the
> answer before they ask the question.
>
> Cheers,
> Mark
Thanks Mark and Emery. I don't think my post was very well written.
One of the ways to increase sound quality in digital audio playback is
reducing jitter. In the following thread, Dynobot brings up how he
used the real-time kernel to reduce latency and improve sound quality:
http://www.computeraudiophile.com/content/Linux-audio
Shouldn't reducing latency reduce jitter and thereby improve sound
quality? I realize we are talking about very small changes in
quality, but I'm interested in seeing Linux fully optimized for
digital audio playback.
- Grant