Note that the wav files have a different sample rate. Firefox goes pulseaudio only, leaves alsa users with no sound. Gentoo forums view topic dsp effects on any player on. Alsa also does oss emulation which is where it tries to fool ossonlyapplications into believing that it alsa is a pukka copy of oss. Warning this settings disables all software mixing. This time i installed pulseaudio rather than just alsa. Alsamixer defaults to the wrong soundcard id 0, since i seem to have one in the computer and another right on the graphics card. The card does not support hardware mixing, but all processes accessing it run applications that use the alsa library.
And as a bonus if you have a sound card which does hardware mixing you wont be forced to do software mixing like you are with pulseaudio. Alsa supports software mixing with the dmix module. However, i have since experienced one nagging problem. Alsa is the next generation sound drivers suite for linux, that supersedes the old oss open sound system drivers. Previously, i had major problems with sound using my echoaudio mia card. The first step is to follow the official gentoo alsa guide to get alsa.
Can i check somehow if sample rate conversion is currently done with hardware or software. I tried asking over at the official gentoo forums, but its like no one knows how to do it. It is heavily multithreaded and tries to excercise the alsa library and driver quite a bit. The correct device to use on outofthebox alsa setups is default. Software mixing with alsa and echoaudio mia audio, gentoo add comments. Sound input to the alsa drivers are eventually fed from an audio backend. So, dmix is not needed anymore, but the solution provided by alsa seem to be a bit unstable still. Previously i blogged about using alsa with echoaudios mia 96khz 24bit prosumer audio card. Asoundrc alsaproject advanced linux sound architecture. I am not using ac3, but have been jack running all the time from years. Otherwise the modern alsa does software mixing by default and resamples to. Advanced linux sound architecture list alsauser archives. However, my soundcard has no hardware mixing, so ill also need a dmix.
So i have some how messed up my mixer settings for alsa under gentoo linux, so i want to restore the default alsa mixer settings, but i can not seem to find out how to do this. I set up kernel alsa as described in the howto on gentoo. This is the recommended device name for most applications. Ultimately, i used alsas dmix plugin to mix audio streams in software, before feeding it to the card. Audacitys alsa support is the default and considered stable. Will forcing the frequency to 96khz and format to 32bit have any benefits for quality. The most annoying example of this is adobe flash in web browsers, which only seem to use the default device.
Configuring linux sound services with alsa by jim mcintyre in open source on april 4, 2001, 12. With it, users can mix different audio tracks together, record from various sources, edit and the list goes on. Bindings to the alsa simple mixer api in the gentoo packages database. Linux software audio mixing with flightgear flightgear wiki. Pulseaudio or pa for short is a sound server that provides a number of features on top of the lowlevel audio interface alsa on linux, such as. For several years the alsa software was developed separately from linux. Advanced linux sound architecture alsa is a software framework and part of the linux kernel that provides an application programming interface api for sound card device drivers some of the goals of the alsa project at its inception were automatic configuration of soundcard hardware and graceful handling of multiple sound devices in a system. It enables sound mixing even on hardware that doesnt support this directly. The default device will usually use pulseaudio or dmix, i. So, sorry, sparriskrigaren, if i set you on the wrong track. And when i want to watch dvds, theyre already at 48 khz so theres no resampling. Devicenames alsaproject advanced linux sound architecture. Alsa offers advanced features such as software mixing for audio cards.
Gentoo linux documentation gentoo linux alsa guide. The intention of the software is to provide a complete audio editing suite suitable for professional use. Portal running on linux gentoo with steam native youtube. There are many ways to have software mixing in the linux environment. Painless sound mixing using alsa gentoo forums view topic.
Alsa software is a software services company specializing in taxation software s, administration related software and catering to specialized needs of chartered. There is a default device thats what its called that most alsa apps will use and it does no software mixing, meaning one app can block access to sound hardware by another. It allows software mixing in an easy to use syntax and without the hassle of installingunderstanding a new application first. One solution is to configure your kernel and alsa according to jack installation instructions for providing low latency audio. Currently, alsa software mixing can handle multiple applications connecting to it with arbitary rates it will then resample these streams and send output to the channel at a specific, rate for default alsa dmix, this is specified in. The only feature that i dont have working is clipboardsharing, but thats a problem for another day. Regardless of your mixer sound level settings, the test sound will play at full volume. Is it possible to somehow mix them and play with alsa on the same output device. It has some very interesting features unique to linuxunix players. Iirc alsa didnt even feature the software mixing plugin in the beginning and. Then, when i want to listen to youtube or whatever, i still get the benefits of software mixing while not caring about the quality because, uh, its youtube. Ardour is a free, open source audio workstation for mac, linux, and windows.
Since alsa is said to be already very efficient and low latency, providing very good quality playback with no additional mixing when stated within its. The alsa guide on the main site will be redirecting to this page. You cannot use old oss software with the alsa devices, unless you convince this software to use alsa instead of oss. Borderlands 2 sp running on linux gentoo with steam. Hardware mixing, software mixing from the alsa wiki.
Im playing with a console sound visualiser which wants its own alsa device to listen on. Therefore, adding a user to the audio group is not recommended by default. In this case, it is fairly easy to create an alsa library configuration file see the. Software mixing with alsa and echoaudio mia trevors it blog. The project was started because the oss architecture is technically weak in some respects, and the free variant of oss lacks some drivers available only in the commercial variant. Pulseaudio is a much more modern and powerful system than alsa in many ways. Alsa software has swiftly grown in the computer software industry in span of time, since its formation in 1993. I trying to play two wav files at the same time using alsa. Alsa when software mixing is enabled, alsa is forced to resample everything to the same. You can find the name of the cards with cat procasoundcards regards, hans.
Solved software mixing with alsa multimedia and games. Firefox goes pulseaudio only, leaves alsa users with no. If your soundcard does not support hw mixing check in the soundcard matrix, aoss and dmixplugin may help you. Advanced linux sound architecture library in the gentoo packages database. I read it may be possible using the mixer but im finding it difficult to understand given the lack of documentation. To get around this, i have to set it to choose card 1 in. This applies to many, many distributions and should work regardless of the tools you prefer.
If any content of the guide is needed reuse, you can find the wikified version in my user space. Introduction to alsa firmware the alsa firmware package contains firmware for certain sound cards this package is known to build and work properly using an. Gentoo forums view topic howto fix poor sound quality. Audacious includes a ladspa host, which can do many dsp effects on an audio stream.
The advanced linux sound architecture alsa uses the kernel to implement lowlevel but extremely powerful audio and midi features. Gentoo provides an alsa use flag which you should set in etcnf to. This article describes, with a soundcard that does not do hardware mixing, how you can run flightgear with other audio applications, such as festival for texttospeech and running teamspeak at the same time, with alsa software mixing dmix and dsnoop plugin. I am having trouble getting alsa to feed audio to my dac via usb. This provides software mixing and resampling of multiple streams as found on other operating systems, and is a good alternative to a sound server. These days we have a native plugin for alsa called the dmix direct mixing plugin. I recently did a fresh install of arch on my tower and my thinkpad.
Download gnomealsamixer packages for alt linux, debian, mageia, openmandriva, ubuntu. A very interesting and potentially extremely useful aspect of this plugin is using it combined with the default plugin name. This contains among other utilities the alsamixer and amixer utilities. Btw does anyone knows what has become of the alsa software mixing support. This is achieved using the dmix for output and dsnoop for input plugins, and asym to. Alsa provides several useful applications, but i like to think of alsa as a tool to build higher level tools.
Software mixing adds latencies, and doesnt work reliably with oss emulation. I am not going into a great deal of detail to keep it short and easy to read for average users, dont expect alsa vs oss vs jack vs pipe discussions. This may break software mixing or fastuserswitching on multiseat systems. So i thought its the same bug, but it seems the sample rate settings bug is fixed and the dxs driver part is now buggy.
Alsa software is a software services company specializing in taxation softwares, administration related software and catering to specialized needs of chartered. Configuring linux sound services with alsa techrepublic. You probably havent heard about jack and alsa before, so a little explaining is in order. Dmix alsa opensrc org independent alsa and linux audio. Dynamic latency adjustment, which can be used to save power. Alsa, the advanced linux sound architecture, is both a project and a body of software.