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Sound in 2007 (JACK server)
please leave me tell you about the sound in 2007 Mandriva-Linux version. ...
I ever use Jack sound server. I ever compil a vanilla kernel with Sir Ingo Molnar' s hard realtime patch (to have "preemption on acid kernel", vanilla kernel works fine with all my hardware, i am a lucky man) I note that is not really need to have a real "professionnal" system for audionumeric signal treatment. Use the realtime module is suffice (inclued in multimedia precompiled kernel) I use KDE.
For this reasons, i never have full features : for example Arts kde sound' s frameworks could route to Jack, but never works really fine (normal) : A warning sound like "humhum" sound from konversation when my nickname is write on irc channel cause many Xrun to alsa… It is the same situation for all kde sound, for videos and music players softwares who works with arts.
This is not confortable
More, a flash animation in a web page, with sounds contains, can' t play sound/music. Because Flash proprietary and closed player attack OSS (bullshit). So, we need to liberate sound device to have music from flash. On top of Alsa soundcard, flash player is routed to aoss compatibility (alsa perform this one to have confort).
But this not perfect too...
If the soundcard don' t have a real harware mixer, we can' t have direct Alsa mixing functionnalities (Alsa is not a mixer). So many users have trouble to have differents woftwares who wants to attack directly Alsa. Only one could open device. And other have no access. This is solved with frameworks ala Arts/Phonon (or esd/pulseaudio on gnome). Applications could have a way to find a mixer. But what about applications want a more direct way ? Arts simply could liberate sound device very quickly just after last use.
But it is not confortable, no 2 apps for alsa direct access in same time (without a real hw mixer)
Alsa project provide th D-Mix plugin. This last give to alsa a mixing feature value. D-mix is really a full features goody. But configure alsa (with ~/.asoundrc file) is not real simply way for end-users.
Not confortable, again.
So, i need to stop Jack when a flash anim want to launch music. I need to configure arts to stop automaticly when it is not used just after 1 second. I need to configure asoundrc file for my card(s)
And for real music usage, i need to simply stop Arts. We know Arts / esd / phonon / Pulseaudio are for "mickey mouse men"...
-> All works fine, yes, but could be better.
Now, what is the news in 2007 ?
I configure arts to route to Jack sound Server. I launch jack (and qjackctl) automaticly at ever desktop session. And no more...
What surprises !!!!!!!!!!!
- First : No Alsa Xrun from Artswhen Jack is running as master !
- Second : D-mix is full configured, integrated (without need to have a special asoundrc file)
- Third : Music from flash ? launch trough soundwrapper perfectly ever time. What route ! flash -> rerouted for arts -> arts routed to jack -> jack to alsa == ?? no Xrun !!!
- Fourthly : switch between tty1 to 6 and 7 to 9(desktops) ? no more xrun !!! (switch between tty1 and desktop cause severals Xrun before this 2007)
- Quinto : Mplayer browser plugin works perfectly, without time-loose, to route to Jack ever audio/video needs.
- Finally : all works fine i never see that before.
I am really impress ! really really !
- thanks GNU and LAUD to have created the best Audio softwares.
- thanks to Mandriva to perform this integration (and all drak X tools who fine down my life !)
- i hope the news features recently added (like priority unheritance) to vanilla kernel prefigure the complete hard rt option. (to have the Mr Love patch, the Mr Morton patch and, near futur, the Mr Molnar patch too)
Version 1.46 last modified by bubar on 30/11/2006 at 13:37
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Comments (5)
The thing is, although I know that many people use kernel-multimedia for various reasons, I never get much feedback from people who really (semi)professionally use sound. Perhaps they all compile their own kernels. I'd like to have someone testing it, because, even although I use preemption and much of the ck stuff in the kernel, I am not really a sound freak, so I never actually get to test what are the latencies (sometimes I do benchmarks though).
It's be wonderful if someone would do that now and then.
mandriva provides, trought non-official kernel-multimedia, some realtime goodies in this kernels. Based on Mr Love or Mr Morton patches (wiches are inclueded by default in kernel vanilla). Good thing, but unfortunatly kernel multimedia are follow the version only in cooker. (in 2006 there are very old) note : this patches works with realtime module and have a soft-rt.
I hope you be happy to learn some contributors provides now a complete realtime preemption on acid kernel with Sir Molnar patch :))) This kernel is just vanilla kernel !! (no all patches into kernel-mandriva or kernel-multimedia for Mandriva) right now, but good is his existance ! no more compile needed :) gain time ) Actually we have a 2.6.18-rt5 who works fine please take a look : http://www.zarb.org/~trem/kernel-rt/
i hope many steps in kernel vanilla last year contineous.. and i hope we could have the complete preemption on acid Molnar patch by defauls in option in kernel vanilla. With that, we could simply use our great mandriva kernel full patch, choice option and recompile ! (not have only a vanilla + rt or applies on 300 patches...)
This sounds ;-) fine, but for my own I have several problems using sound.
First I can't figure out how to mix Java sound. Seems Java applets take exclusive usage of /dev/dsp. Is there is a way to route java sound to alsa ? I read somewhere that java now support alsa… but how to make it work together ?
Other problem : In addition to my AC'97 onboard sound chipset, I have a microphone with my usb webcam (QuickCam 4000 Pro). I load the two drivers (snd-usb for microphone) but I have lot of problems to make recording sound work with other apps than Audacity. With Audacity, I can choose my input device, so I specify alsa hw:1.0 device and all works fine, but with other apps I can't make it works. Maybe is it because they try to access sound trough OSS compatibility layer...
Any Clue ?
For 2008 I think we will probably have Ingo's work activated in kernel-multimedia.
And no I'm not Thomas, he maintains tmb, not -multimeda. Although he helps me out quite often.