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1<?xml version='1.0' encoding="UTF-8"?> 1<?xml version='1.0' encoding="UTF-8"?>
2<!-- $Header: /var/cvsroot/gentoo/xml/htdocs/doc/en/alsa-guide.xml,v 1.21 2003/11/23 16:30:50 swift Exp $ --> 2<!-- $Header: /var/cvsroot/gentoo/xml/htdocs/doc/en/alsa-guide.xml,v 1.78 2007/05/06 23:27:46 nightmorph Exp $ -->
3
3<!DOCTYPE guide SYSTEM "/dtd/guide.dtd"> 4<!DOCTYPE guide SYSTEM "/dtd/guide.dtd">
4 5
5<guide link = "/doc/en/alsa-guide.xml"> 6<guide link="/doc/en/alsa-guide.xml">
6<title>Gentoo Linux ALSA Guide</title> 7<title>Gentoo Linux ALSA Guide</title>
8
7<author title="Author"> 9<author title="Author">
8 <mail link="zu@pandora.be">Vincent Verleye</mail> 10 <mail link="fox2mike@gentoo.org">Shyam Mani</mail>
9</author> 11</author>
10<author title="Author"> 12<author title="Author">
11 <mail link="g2boojum@gentoo.org">Grant Goodyear</mail> 13 <mail link="nightmorph@gentoo.org">Joshua Saddler</mail>
12</author> 14</author>
13<author title="Author"> 15<author title="Contributor">
14 <mail link="agenkin@gentoo.org">Arcady Genkin</mail> 16 <mail link="flameeyes@gentoo.org">Diego PettenĂ²</mail>
15</author> 17</author>
16<author title="Editor"><!-- zhen@gentoo.org -->
17 John P. Davis
18</author>
19<author title="Editor">
20 <mail link="swift@gentoo.org">Sven Vermeulen</mail>
21</author>
22<author title="Editor">
23 <mail link="bennyc@gentoo.org">Benny Chuang</mail>
24</author>
25<author title="Editor">
26 <mail link="blubber@gentoo.org">Tiemo Kieft</mail>
27</author>
28 18
19<abstract>
20This document helps a user setup ALSA on Gentoo Linux.
21</abstract>
22
23<!-- The content of this document is licensed under the CC-BY-SA license -->
24<!-- See http://creativecommons.org/licenses/by-sa/2.5 -->
29<license/> 25<license/>
30 26
31<abstract>
32This guide will show you how to set up the Advanced Linux Sound Architecture
33(ALSA) on Gentoo Linux. In addition to the Gentoo Linux Desktop Configuration
34Guide, this guide is supposed to give you more information on this subject.
35</abstract>
36
37<version>1.3.4</version> 27<version>2.21</version>
38<date>November 23, 2003</date> 28<date>2007-05-06</date>
39 29
40<chapter> 30<chapter>
41<title>Introduction</title> 31<title>Introduction</title>
42<section> 32<section>
43<title>What is ALSA?</title> 33<title>What is ALSA?</title>
44<body> 34<body>
45 35
46<p> 36<p>
47The Advanced Linux Sound Architecture (ALSA) is a project to improve the Linux 37ALSA, which stands for <e>Advanced Linux Sound Architecture</e>, provides
48sound subsystem by rewriting large chunks of it. It is anticipated that ALSA 38audio and MIDI (<e>Musical Instrument Digital Interface</e>) functionality to
49will make it into Linux kernel 2.6.x (or 3.x.x -- whichever comes first) as it 39the Linux operating system. ALSA is the default sound subsystem in the 2.6
50becomes ready. 40kernel thereby replacing OSS (<e>Open Sound System</e>), which was used in the
51</p> 412.4 kernels.
52
53<p> 42</p>
54ALSA provides audio and MIDI functionality for Linux. 43
55</p> 44<p>
56 45ALSA's main features include efficient support for all types of audio
46interfaces ranging from consumer sound cards to professional sound
47equipment, fully modularized drivers, SMP and thread safety, backward
48compatibility with OSS and a user-space library <c>alsa-lib</c> to make
49application development a breeze.
57<p> 50</p>
58Quoted from <uri>http://www.alsa-project.org</uri>, ALSA has the following 51
59features: 52</body>
53</section>
54<section>
55<title>ALSA on Gentoo</title>
56<body>
57
58<p>
59One of Gentoo's main strengths lies in giving the user maximum control over
60how a system is installed/configured. ALSA on Gentoo follows the same
61principle. There are two ways you can get ALSA support up and running on your
62system. We shall look at them in detail in the next chapter.
63</p>
64
65</body>
66</section>
67</chapter>
68
69<chapter>
70<title>Installing ALSA</title>
71<section>
72<title>Options</title>
73<body>
74
75<warn>
76The methods shown below are mutually exclusive. You cannot have ALSA compiled
77in your kernel and use <c>media-sound/alsa-driver</c>. It <e>will</e> fail.
78</warn>
79
80<p>
81The two options are :
82</p>
83
84<ol>
85 <li>
86 Use ALSA provided by your kernel. This is the preferred/recommended method.
87 </li>
88 <li>Use Gentoo's <c>media-sound/alsa-driver</c> package.</li>
89</ol>
90
91<p>
92The in-kernel drivers and the <c>alsa-driver</c> package can vary a little; it's
93possible that features and fixes found in one might not yet be incorporated into
94the other. The upstream developers are aware of this, but the two drivers are
95effectively separate branches of the ALSA project; they are not entirely
96identical. You should be aware that they might function slightly differently, so
97if one doesn't work for you, try the other! We shall take a peek into both
98before finally deciding on one.
99</p>
100
101<p>
102If you were to use ALSA provided by the kernel, the following are the pros and
103cons :
104</p>
105
106<table>
107<tr>
108 <th>Kernel ALSA</th>
109 <th>Pros and Cons</th>
110</tr>
111<tr>
112 <th>+</th>
113 <ti>
114 No need to emerge yet another package; drivers are integrated into kernel.
115 </ti>
116</tr>
117<tr>
118 <th>+</th>
119 <ti>One shot solution, no repeating emerges.</ti>
120</tr>
121<tr>
122 <th>-</th>
123 <ti>Might be a slightly different version than <c>alsa-driver</c>.</ti>
124</tr>
125</table>
126
127<p>
128And, if you were to use <c>alsa-driver</c>,
129</p>
130
131<table>
132<tr>
133 <th>alsa-driver</th>
134 <th>Pros and Cons</th>
135</tr>
136<tr>
137 <th>+</th>
138 <ti>Possibly the latest drivers from the ALSA Project.</ti>
139</tr>
140<tr>
141 <th>+</th>
142 <ti>Useful if you intend to develop audio drivers.</ti>
143</tr>
144<tr>
145 <th>-</th>
146 <ti>Every kernel recompile requires a re-emerge of <c>alsa-driver</c>.</ti>
147</tr>
148<tr>
149 <th>-</th>
150 <ti>Needs certain kernel config options disabled to work correctly.</ti>
151</tr>
152</table>
153
154</body>
155</section>
156<section>
157<title>So...</title>
158<body>
159
160<p>
161The differences between <c>alsa-driver</c> and the in-kernel ALSA drivers are
162quite subtle, as mentioned earlier. Since there are not any huge differences,
163you are encouraged to go through the process of using the ALSA provided by the
164kernel <e>first</e> for ease of use. Before reporting any sound related issues
165to <uri link="https://bugs.gentoo.org">Gentoo Bugzilla</uri>, please try to
166reproduce them using <c>alsa-driver</c> and file the bug report no matter what
167the result.
168</p>
169
170</body>
171</section>
172<section id="lspci">
173<title>Before you proceed</title>
174<body>
175
176<p>
177Whichever method of install you choose, you need to know what drivers your
178sound card uses. In most cases, sound cards (onboard and otherwise) are PCI
179based and <c>lspci</c> will help you in digging out the required information.
180Please <c>emerge sys-apps/pciutils</c> to get <c>lspci</c>, if you don't have it
181installed already. In case you have a USB sound card, <c>lsusb</c> from
182<c>sys-apps/usbutils</c> <e>might</e> be of help. For ISA cards, try using
183<c>sys-apps/isapnptools</c>. Also, the following pages <e>may</e> help users
184with ISA based sound cards.
60</p> 185</p>
61 186
62<ul> 187<ul>
63 <li> 188 <li>
64 Efficient support for all types of audio interfaces, from consumer 189 <uri link="http://www.roestock.demon.co.uk/isapnptools/">The ISAPNPTOOLS
65 soundcards to professional multichannel audio interfaces 190 Page</uri>
66 </li>
67 <li>Fully modularized sound drivers</li>
68 <li>SMP and thread-safe design</li>
69 <li>
70 User space library (alsa-lib) to simplify application programming and
71 provide higher level functionality
72 </li> 191 </li>
73 <li> 192 <li>
74 Support for the older OSS API, providing binary compatibility for most OSS 193 <uri link="http://www2.linuxjournal.com/article/3269">LinuxJournal PnP
75 programs 194 Article</uri>
76 </li> 195 </li>
196 <li>
197 <uri link="http://www.tldp.org/HOWTO/Sound-HOWTO/x320.html">TLDP Sound
198 HowTo</uri>
199 </li>
77</ul> 200</ul>
78 201
79<p> 202<note>
80There's lots more to ALSA however, like support for Full Duplex playback and 203For ease of use/explanation, we assume the user has a PCI based sound card for
81recording, multiple soundcard support, hardware mixing of streams, extensive 204the remainder of this guide.
82mixer capabilities (to support advanced features of new soundcards), ... 205</note>
206
83</p> 207<p>
208We now proceed to find out details about the sound card.
209</p>
84 210
211<pre caption="Soundcard Details">
212# <i>lspci -v | grep -i audio</i>
2130000:00:0a.0 Multimedia audio controller: Creative Labs SB Live! EMU10k1 (rev 06)
214</pre>
215
216<p>
217We now know that the sound card on the machine is a Sound Blaster Live! and the
218card manufacturer is Creative Labs. Head over to the <uri
219link="http://bugtrack.alsa-project.org/main/index.php/Matrix:Main">ALSA
220Soundcard Matrix</uri> page and select Creative Labs from the drop down menu.
221You will be taken to the Creative Labs matrix page where you can see that the SB
222Live! uses the <c>emu10k1</c> module. That is the information we need for now.
223If you are interested in detailed information, you can click on the link next to
224the "Details" and that will take you to the <c>emu10k1</c> specific page.
225</p>
226
227<p>
228If you intend to use MIDI, then you should add <c>midi</c> to your USE flags in
229<path>/etc/make.conf</path> before emerging any ALSA packages. Later in the
230guide, we will show you how to set up <uri link="#midi">MIDI support</uri>.
231</p>
232
85</body> 233</body>
86</section>
87<section> 234</section>
88<title>Why use ALSA?</title> 235<section id="kernel">
89<body> 236<title>Using ALSA provided by your Kernel</title>
90
91<p>
92If your soundcard is supported by the Linux kernel sound system or the
93commercial OSS/4Front sound driver system, which can be found in all 2.4.x
94Linux kernels, you could just aswell build <e>those modules</e> for use with
95your soundcard. If you want this, just read through the <uri
96link="http://www.tldp.org/HOWTO/Sound-HOWTO/index.html">Linux Sound HOWTO</uri>.
97</p>
98
99<p>
100However, those OSS/4Front drivers have some limitations -- being commercial is
101one. ALSA is an attempt to go beyond these limitations and to do so in an open
102source fashion. ALSA is a fully GPL and LGPL'ed sound driver system, that
103provides a professional quality system for recording, playback, and MIDI
104sequencing.
105</p>
106
107</body> 237<body>
108</section> 238
239<p>
240If you're a person who likes to keep things simple like I do, then this is
241the way to go.
242</p>
243
244<note>
245Since the 2005.0 release, Gentoo Linux uses 2.6 as the default kernel. Unless
246you are specifically using the 2.4 profile, <c>gentoo-sources</c> will be a
2472.6 kernel on <e>most</e> architectures. Please check that your kernel is a
2482.6 series kernel. This method will <e>not</e> work on a 2.4 kernel.
249</note>
250
251<p>
252Let us now configure the kernel to enable ALSA.
253</p>
254
255<impo>
256<c>genkernel</c> users should now run <c>genkernel --menuconfig all</c> and
257then follow the instructions in <uri link="#doc_chap2_pre3">Kernel Options for
258ALSA</uri>.
259</impo>
260
261<pre caption="Heading over to the source">
262# <i>cd /usr/src/linux</i>
263# <i>make menuconfig</i>
264</pre>
265
266<note>
267The above example assumes that <path>/usr/src/linux</path> symlink points to
268the kernel sources you want to use. Please ensure the same before proceeding.
269</note>
270
271<p>
272Now we will look at some of the options we will have to enable in the 2.6
273kernel to ensure proper ALSA support for our sound card.
274</p>
275
276<p>
277Please note that for ease of use, all examples show ALSA built as modules. It
278is advisable to follow the same as it then allows the use of <c>alsaconf</c>
279which is a boon when you want to configure your card. Please do <e>not</e> skip
280the <uri link="#alsa-config">Configuration</uri> section of this document. If
281you still like to have options built-in, ensure that you make changes to your
282config accordingly.
283</p>
284
285<pre caption="Kernel Options for ALSA">
286Device Drivers ---&gt;
287 Sound ---&gt;
288
289<comment>(This needs to be enabled)</comment>
290&lt;M&gt; Sound card support
291
292<comment>(Make sure OSS is disabled)</comment>
293Open Sound System ---&gt;
294 &lt; &gt; Open Sound System (DEPRECATED)
295
296<comment>(Move one step back and enter ALSA)</comment>
297Advanced Linux Sound Architecture ---&gt;
298 &lt;M&gt; Advanced Linux Sound Architecture
299 <comment>(Select this if you want MIDI sequencing and routing)</comment>
300 &lt;M&gt; Sequencer support
301 <comment>(Old style /dev/mixer* and /dev/dsp* support. Recommended.)</comment>
302 &lt;M&gt; OSS Mixer API
303 &lt;M&gt; OSS PCM (digital audio) API
304
305<comment>(You now have a choice of devices to enable support for. Generally,
306you will have one type of device and not more. If you have more than one
307sound card, please enable them all here.)</comment>
308
309<comment>(Mostly for testing and development purposes, not needed for normal
310users unless you know what you are doing.)</comment>
311Generic devices ---&gt;
312
313<comment>(For ISA Sound cards)</comment>
314ISA devices ---&gt;
315<comment>(IF you had the Gravis, you would select this option)</comment>
316 &lt;M&gt; Gravis UltraSound Extreme
317
318<comment>(Move one level back and into PCI devices. Most sound cards today are
319PCI devices)</comment>
320PCI devices ---&gt;
321 <comment>(We now select the emu10k1 driver for our card)</comment>
322 &lt;M&gt; Emu10k1 (SB Live!, Audigy, E-mu APS)
323 <comment>(Or an Intel card would be)</comment>
324 &lt;M&gt; Intel/SiS/nVidia/AMD/ALi AC97 Controller
325 <comment>(Or if you have a VIA Card)</comment>
326 &lt;M&gt; VIA 82C686A/B, 8233/8235 AC97 Controller
327
328<comment>(Move one level back and select in case you have an USB sound card)</comment>
329USB Devices ---&gt;
330</pre>
331
332<p>
333Now that your options are set, you can (re)compile the kernel and ALSA support
334for your card should be functional once you reboot into the new kernel. Don't
335forget to update your GRUB configuration to use the newly built kernel.
336You can now proceed to <uri link="#alsa-utilities">ALSA Utilities</uri> and
337see if everything is working as it should.
338</p>
339
340</body>
109<section> 341</section>
110<title>What cards does ALSA support?</title> 342<section id="alsa-driver">
343<title>Using the ALSA Driver package</title>
111<body> 344<body>
112 345
113<p>
114ALSA tries to support as many (new) cards as possible by providing open-source
115drivers. However, some vendors may provide binary-only packages.
116</p> 346<p>
117 347So you've decided to go the <c>alsa-driver</c> way. Let's get started then.
348There are a few minor things to be done to ensure only the drivers for your
349sound card are compiled. Although this is not really necessary, it cuts down
350on the unnecessary drivers that will be compiled otherwise.
118<p> 351</p>
119To know if your card is supported, you can find a Soundcard Matrix of supported 352
120and not-supported cards here: <uri>http://www.alsa-project.org/alsa-doc/</uri>.
121</p> 353<p>
354If you don't have an idea of what drivers your sound card might need, please
355take a look at the <uri link="#lspci">lspci</uri> section of this guide. Once
356you have your driver name (<c>emu10k1</c> in our example), edit
357<path>/etc/make.conf</path> and add a variable, <c>ALSA_CARDS</c>.
358</p>
359
360<pre caption="Adding ALSA_CARDS to make.conf">
361<comment>(For one sound card)</comment>
362ALSA_CARDS="emu10k1"
363<comment>(For more than one, separate names with spaces)</comment>
364ALSA_CARDS="emu10k1 via82xx"
365</pre>
366
367<p>
368If you have compiled your kernel and want to use <c>alsa-driver</c>, please
369ensure the following before proceeding, else <c>alsa-driver</c> is likely to
370fail. The next code listing gives you one way of performing the checks.
371</p>
372
373<note>
374<c>genkernel</c> users can proceed with <uri link="#doc_chap2_pre6">Installing
375alsa-driver</uri> as their configuration is in sync with the one shown below by
376default.
377</note>
378
379<ol>
380 <li>
381 <c>CONFIG_SOUND</c> is set. (Basic Sound support enabled)
382 </li>
383 <li>
384 <c>CONFIG_SOUND_PRIME</c> is not set. (In-built OSS support disabled)
385 </li>
386 <li>
387 <c>CONFIG_SND</c> is not set. (In-built ALSA support disabled)
388 </li>
389 <li>
390 <path>/usr/src/linux</path> points to the kernel you want ALSA working on.
391 </li>
392</ol>
393
394<pre caption=".config checks">
395<comment>(Assuming the linux symlink points to the correct kernel)</comment>
396# <i>cd /usr/src/linux</i>
397# <i>grep SOUND .config</i>
398<comment>(1. is true)</comment>
399CONFIG_SOUND=y
400<comment>(2. is true)</comment>
401CONFIG_SOUND_PRIME is not set
402# <i>grep SND .config</i>
403<comment>(and 3. is true)</comment>
404CONFIG_SND is not set
405</pre>
406
407<p>
408Now all you have to do is type the magic words... and no, it's not abracadabra.
409</p>
410
411<pre caption="Installing alsa-driver">
412# <i>emerge alsa-driver</i>
413</pre>
414
415<impo>
416Please note that you will have to run <c>emerge alsa-driver</c> after every
417kernel (re)compile, as the earlier drivers are deleted. To make this task
418easier, you may want to emerge the <c>module-rebuild</c> package, which will
419keep track of module packages and rebuild them for you. First run
420<c>module-rebuild populate</c> to create the list, and then after every kernel
421(re)compile, you just run <c>module-rebuild rebuild</c>, and your external
422modules will be rebuilt.
423</impo>
122 424
123</body> 425</body>
124</section> 426</section>
125</chapter> 427</chapter>
126 428
127<chapter> 429<chapter>
128<title>Installation</title> 430<title>Configuring/Testing ALSA</title>
129<section> 431<section id="alsa-utilities">
130<title>Gentoo USE flags</title> 432<title>ALSA Utilities</title>
131<body>
132
133<p>
134To compile programs with ALSA-support, be sure to add <e>alsa</e> to
135your USE-variable. However, several tools don't support alsa yet, and
136require OSS. ALSA provides OSS-emulation if you define <e>oss</e> in your
137USE-variable before you start.
138</p>
139
140</body> 433<body>
141</section>
142<section>
143<title>Kernel modules</title>
144<body>
145 434
146<p>
147Since we're still using 2.4.x kernel sources, we'll have to compile kernel
148modules and ALSA modules separately. People who are using a 2.5.x kernel can
149do this from within their kernel configuration, since the ALSA modules are
150included in the kernel sources and should be built there.
151</p> 435<p>
152 436<c>alsa-utils</c> forms an integral part of ALSA as it has a truckload of
437programs that are highly useful, including the ALSA Initscripts. Hence we
438strongly recommend that you install <c>alsa-utils</c>
153<p> 439</p>
154First we'll make sure that our kernel configuration is ready for use with ALSA. 440
155All you need in your kernel configuration is having Sound Card Support set to 441<pre caption="Install alsa-utils">
156be built as a module (M). This will build <path>soundcore.o</path>. 442# <i>emerge alsa-utils</i>
157</p> 443</pre>
158 444
159<note> 445<note>
160Possibly, this will also work when you built Sound Card Support in the kernel 446If you activated ALSA in your <uri link="#kernel">kernel</uri> <e>and</e> did
161(Y) instead of building it as a module (M). However, the official ALSA 447not compile ALSA as modules, please proceed to the
162documentation suggests building it as a module, since ALSA will try loading it. 448<uri link="#initscript">ALSA Initscript</uri> section. The rest of you need
449to configure ALSA. This is made very easy by the existence of the
450<c>alsaconf</c> tool provided by <c>alsa-utils</c>.
163</note> 451</note>
164 452
165<p> 453</body>
166If you already have a working kernel configuration, make sure you remove all 454</section>
167sound drivers (except for Sound Card Support). If you wish to do this without 455<section id="alsa-config">
168having to reboot, you could do like this: 456<title>Configuration</title>
457<body>
458
169</p> 459<p>
170 460Recent versions of <c>udev</c> (<c>>=udev-103</c>) provide some degree of
171<pre caption="Kernel configuration"> 461kernel-level autoconfiguration of your sound card. If possible, try to rely on
172# <i>cd /usr/src/linux</i> 462just letting your kernel automatically setup your sound card for you. Otherwise,
173# <i>cp .config ~/</i> 463use <c>alsaconf</c> to configure your card, as shown below.
174# <i>make mrproper</i>
175# <i>cp ~/.config .</i>
176# <i>make menuconfig</i>
177</pre>
178
179<p> 464</p>
180Now select <e>Sound Card Support</e> as Module (M) and deselect all other sound 465
181drivers. Exit and say Y to save your kernel configuration. After that, build 466<note>
182the modules: 467Please shut down any programs that <e>might</e> access the sound card while
468running <c>alsaconf</c>.
469</note>
470
183</p> 471<p>
184 472Another way to configure your sound card is to run <c>alsaconf</c>. Just type
185<pre caption="Kernel compilation"> 473<c>alsaconf</c> in a shell as root.
186# <i>make dep clean</i>
187# <i>make modules modules_install</i>
188</pre>
189
190<p> 474</p>
191Before installing your new modules, this last line will delete all your previous 475
192modules, even the ones from a previous ALSA installation. 476<pre caption="Invoking alsaconf">
477# <i>alsaconf</i>
478</pre>
479
193</p> 480<p>
481You will now see a neat menu guided interface that will automatically probe
482your devices and try to find out your sound card. You will be asked to pick
483your sound card from a list. Once that's done, it will ask you permission to
484automatically make required changes to <path>/etc/modules.d/alsa</path>.
485It will then adjust your volume settings to optimum levels, run
486<c>update-modules</c> and start the <path>/etc/init.d/alsasound</path> service.
487Once <c>alsaconf</c> exits, you can proceed with setting up the ALSA
488initscript.
489</p>
490
491</body>
492</section>
493<section id="initscript">
494<title>ALSA Initscript</title>
495<body>
496
497<p>
498We're now almost all setup. Whichever method you chose to install ALSA, you'll
499need to have something load your modules or initialize ALSA and restore your
500volume settings when your system comes up. The ALSA Initscript handles all of
501this for you and is called <c>alsasound</c>. Add it to the boot runlevel.
502</p>
503
504<pre caption="Adding ALSA to the boot runlevel">
505# <i>rc-update add alsasound boot</i>
506 * alsasound added to runlevel boot
507 * rc-update complete.
508</pre>
509
510<p>
511Next, just check the <path>/etc/conf.d/alsasound</path> file and ensure that
512SAVE_ON_STOP variable is set to yes. This saves your sound settings when you
513shutdown your system.
514</p>
515
516</body>
517</section>
518<section>
519<title>Audio Group</title>
520<body>
521
522<p>
523Before we move on to testing, there's one last <e>important</e> thing that needs
524to be setup. Rule of thumb in a *nix OS : Do not run as root unless needed.
525This applies here as well ;) How? Well, most of the times you should be logged
526in as a user and would like to listen to music or access your soundcard. For
527that to happen, you need to be in the "audio" group. At this point, we'll add
528users to the audio group, so that they won't have any issues when they want to
529access sound devices. We'll use <c>gpasswd</c> here and you need to be logged in
530as root for this to work.
531</p>
532
533<pre caption="Adding users to the audio group">
534<comment>(Substitute &lt;username&gt; with your user)</comment>
535# <i>gpasswd -a &lt;username&gt; audio </i>
536Adding user &lt;username&gt; to group audio
537</pre>
538
539</body>
540</section>
541<section>
542<title>Volume Check!</title>
543<body>
544
545<p>
546We've completed all the setups and prerequisites, so let's fire up ALSA. If
547you ran <c>alsaconf</c>, you can skip this step, since <c>alsaconf</c> already
548does this for you.
549</p>
550
551<pre caption="Start the service">
552# <i>/etc/init.d/alsasound start</i>
553</pre>
554
555<p>
556Now that the required things have been taken care of, we need to check up on
557the volume as in certain cases, it is muted. We use <c>alsamixer</c> for this
558purpose.
559</p>
560
561<pre caption="Starting alsamixer">
562<comment>(Opens up a console program. Only required settings are shown)</comment>
563# <i>alsamixer</i>
564</pre>
194 565
195<impo> 566<impo>
196This means, whenever you recompile your kernel later on, you MUST recompile 567If you have issues starting up <c>alsamixer</c> and get errors such as
197<c>alsa-driver</c>. 568alsamixer: function snd_ctl_open failed for default: No such file or directory,
569this is usually an issue with udev setting up the devices. Run <c>killall
570udevd; udevstart</c> to reload <path>/dev</path> entries and fire up
571<c>alsamixer</c>. It should solve the issue.
198</impo> 572</impo>
199 573
200</body>
201</section>
202<section>
203<title>ALSA modules</title>
204<body>
205
206<p>
207Now it's time to install the ALSA drivers for your soundcard(s). If your
208soundcard is PCI, you can find out the name and type of your soundcard by
209looking at the output of <path>/proc/pci</path>.
210</p> 574<p>
211 575This is how the ALSA Mixer <e>might</e> look the first time you open it. Pay
212<pre caption="Search for soundcard information"> 576attention to the Master and PCM channels which both have an MM below them.
213# <i>grep audio /proc/pci</i> 577That means they are muted. If you try to play anything with <c>alsamixer</c>
578in this state, you will not hear anything on your speakers.
214</pre> 579</p>
580
581<figure link="/images/docs/alsa-mixermuted.png" short="AlsaMixer Muted" caption="The Alsa Mixer Main Window, Muted"/>
582
583<p>
584Now, we shall unmute the channels, and set volume levels as needed.
585</p>
215 586
216<warn> 587<warn>
217If you had a previous sound setup and there are still non-ALSA sound modules 588Both Master <e>and</e> PCM need to be unmuted and set to audible volume levels
218loaded, unload them <e>now</e>. Check with <c>lsmod</c> and use <c>rmmod</c> 589if you want to hear some output on your speakers.
219to unload all sound-related modules on your system.
220</warn> 590</warn>
221
222<p>
223We could simply do an <c>emerge alsa-driver</c> now, this would compile and
224install <e>all</e> ALSA sound drivers.
225</p>
226
227<p>
228However, to save some time, lookup the <e>Module Name</e> of your soundcard(s)
229on the <uri link="http://www.alsa-project.org/alsa-doc">ALSA Soundcard
230Matrix</uri> by following the <e>Details</e> link in the <e>Driver and Docs</e>
231column in the row of the chipset of your soundcard. Mine is <c>snd-emu10k1</c>,
232since I have an SBlive! soundcard, with the <e>EMU10K1</e> chipset. We'll set
233ALSA_CARDS environment to the value of the module name before emerging (but
234without the snd prefix), so emerge will only compile the drivers we need.
235</p>
236
237<pre caption="Compile correct modules">
238# <i>env ALSA_CARDS='emu10k1' emerge alsa-driver</i>
239</pre>
240
241<note>
242You can also add this value in <path>/etc/make.conf</path>, so when you have
243to emerge the alsa-driver later on you can just run <c>emerge alsa-driver</c>.
244For example, like this: <c>echo 'ALSA_CARDS="emu10k1"' >> /etc/make.conf</c>
245</note>
246
247<note>
248When you want to install ALSA drivers for more than one soundcard, you could
249set ALSA_CARDS to a space-separated list of drivers; like this: <c>env
250ALSA_CARDS='emu10k1 intel8x0 ens1370' emerge alsa-driver</c>
251</note>
252
253<note>
254If you want to have OSS compatibility, make sure to emerge <i>alsa-oss</i>, it
255is the ALSA/OSS compatibility wrapper.
256</note>
257
258<note>
259If you plan on recompiling your kernels numerous times, it might
260be adviseable to emerge <c>alsa-driver</c> with <c>--buildpkg</c>. This
261will create a binary package for it. Later, after recompiling your kernel,
262you can just do <c>emerge --usepkg alsa-driver</c> which will install the
263binary package instead of recompiling it completely.
264</note>
265
266<p>
267After this, the ALSA modules should be installed on your system.
268</p>
269
270</body>
271</section>
272<section>
273<title>Configuration of ALSA</title>
274<body>
275
276<p>
277Let's start configuring now to get ALSA working properly. We'll need to edit
278some files, to let our system know about the freshly installed ALSA modules.
279</p>
280
281<p>
282First, install <c>alsa-utils</c> on your system:
283</p>
284
285<pre caption = "Emerging alsa-utils">
286# <i>emerge alsa-utils</i>
287</pre>
288
289<p>
290Hereafter, we need to edit <path>/etc/modules.d/alsa</path>.
291</p>
292
293<warn>
294There is no need to edit <path>/etc/modules.conf</path>. Instead, always edit
295files in <path>/etc/modules.d</path>.
296</warn>
297
298<p>
299Check the ALSA portion <e>at the bottom of the file</e>. By tweaking this line
300you can specify the max number of soundcards you have (generally, just one).
301</p>
302
303<pre caption="At the bottom of /etc/modules.d/alsa">
304<comment>Set this to the correct number of cards.</comment>
305options snd cards_limit=1
306</pre>
307
308<p>
309Now we'll specify the sounddriver(s) ALSA should use. In the same file, edit
310like this:
311</p>
312
313<pre caption="In /etc/modules.d/alsa">
314## and then run `modules-update' command.
315## Read alsa-driver's INSTALL file in /usr/share/doc for more info.
316##
317## ALSA portion
318alias snd-card-0 snd-emu10k1
319<comment>## If you have more than one, add:</comment>
320## alias snd-card-1 snd-intel8x0
321## alias snd-card-2 snd-ens1370
322## OSS/Free portion
323## alias sound-slot-0 snd-card-0
324## alias sound-slot-1 snd-card-1
325##
326</pre>
327
328<note>
329If you have more than one soundcard, adjust the <c>cards_limit</c> value and add
330more snd-card aliases to the file. I don't have experience with this, but you
331can find examples for configurations with two or more soundcards in <uri
332link="http://www.alsa-project.org/alsa-doc/alsa-howto/c1660.htm">Chapter 6</uri>
333of the <uri
334link="http://www.alsa-project.org/alsa-doc/alsa-howto/alsa-howto.html">ALSA
335Howto</uri>.
336</note>
337
338<p>
339Last thing to do in this file, almost at the end, check if these lines are there
340and uncommented:
341</p>
342
343<pre caption="Near the end of /etc/modules.d/alsa">
344alias /dev/mixer snd-mixer-oss
345alias /dev/dsp snd-pcm-oss
346alias /dev/midi snd-seq-oss
347</pre>
348
349<p>
350Now double-check the file <path>/etc/modules.d/alsa</path> and when you're sure
351everyting is ok, run <c>modules-update</c>.
352</p>
353
354<pre caption="Running modules-update">
355# <i>modules-update</i>
356</pre>
357
358<note>
359Running <c>modules-update</c> here will insert the data from
360<path>/etc/modules.d/alsa</path> into <path>/etc/modules.conf</path>
361</note>
362
363<p>
364You should also verify that <path>/etc/devfsd.conf</path> has the alsa devices
365and permissions correctly registered.
366</p>
367
368<pre caption="/etc/devfsd.conf">
369# ALSA/OSS stuff
370# Comment/change these if you want to change the permissions on
371# the audio devices
372LOOKUP snd MODLOAD ACTION snd
373LOOKUP dsp MODLOAD
374LOOKUP mixer MODLOAD
375LOOKUP midi MODLOAD
376REGISTER sound/.* PERMISSIONS root.audio 660
377REGISTER snd/.* PERMISSIONS root.audio 660
378</pre>
379
380<note>
381Notice that devfsd.conf sets <path>/dev/sound</path> permissions to be
382root.audio. Thus, for non-root users to use audio they will have to be part of
383the audio group.
384</note>
385
386</body>
387</section>
388</chapter>
389
390<chapter>
391<title>Starting ALSA</title>
392<section>
393<title>Adding alsasound to a runlevel</title>
394<body>
395
396<p>
397First thing to do now, is to make ALSA startup at boottime. Like this:
398</p>
399
400<pre caption="Add ALSA to the default runlevel">
401# <i>rc-update add alsasound boot</i>
402</pre>
403
404<warn>
405Note that the alsasound script should be added to the "boot" runlevel, not the
406"default" runlevel.
407</warn>
408
409</body>
410</section>
411<section>
412<title>Running and unmuting</title>
413<body>
414
415<p>
416Since we're Linux users, we don't want to reboot. So we'll start the alsasound
417script manually.
418</p>
419
420<pre caption="Starting ALSA">
421# <i>/etc/init.d/alsasound start</i>
422</pre>
423
424<p>
425ALSA is running now. If everything is ok, you should be able to see the ALSA
426modules loaded when running <c>lsmod</c>. However, sound won't work yet,
427because the channels are still muted. We need <c>amixer</c> for this.
428</p>
429
430<pre caption = "Running amixer">
431# <i>amixer</i>
432</pre>
433
434<warn>
435You shouldn't get this, but <e>if</e> you get an error about "amixer: Mixer
436attach default error: No such file or directory", you should manually modprobe
437<c>snd-mixer-oss</c> and <c>snd-pcm-oss</c> once. After that run amixer again.
438</warn>
439
440<pre caption="Only if you get an error when running amixer">
441# <i>modprobe snd-mixer-oss</i>
442# <i>modprobe snd-pcm-oss</i>
443# <i>amixer</i>
444</pre>
445
446<p>
447If you got this far, now unmute Master and PCM channels. Some hardware
448even requires you to unmute the center channel or even the surround
449channel.
450</p>
451
452<pre caption = "Unmuting channels">
453# <i>amixer set Master 100 unmute</i>
454# <i>amixer set PCM 100 unmute</i>
455<comment>Only if the above doesn't succeed on its own:</comment>
456# <i>amixer set Center 100 unmute</i>
457# <i>amixer set Surround 100 unmute</i>
458<comment>Test the sound:</comment>
459# <i>aplay $KDEDIR/share/sounds/pop.wav</i> <codenote>(pop.wav is part of KDE)</codenote>
460</pre>
461
462<p>
463We check to see if sound is working by using the aplay (alsa play) command. If
464you hear a pop, then sound is indeed working. Then, adjust the volume settings
465to your liking; the ncurses-based <c>alsamixer</c> is a great way to get them
466"just so".
467</p>
468
469<p>
470You may want to emerge <c>alsa-xmms</c> as that will provide ALSA support for
471XMMS.
472</p>
473
474<p>
475When you reboot your system, the <c>alsasound</c> init script will properly saveand restore your volume settings.
476</p>
477
478</body>
479</section>
480</chapter>
481
482<chapter>
483<title>Final Notes</title>
484<section>
485<title>After kernel-upgrades..</title>
486<body>
487
488<p>
489When you ever rebuild your kernel, or upgrade to another kernel, you'll have to
490rebuild the ALSA modules.
491</p>
492
493<p>
494Although you might have installed <c>alsa-driver</c>, <c>alsa-libs</c> and
495<c>alsa-utils</c>, only the first will have to be installed again, since it will
496put the alsa modules in <path>/lib/modules/*/kernel/sound/pci/</path>.
497</p>
498
499<pre caption="needed after each kernel compile">
500# <i>emerge alsa-driver</i>
501</pre>
502
503</body>
504</section>
505<section>
506<title>/etc/modules.autoload</title>
507<body>
508
509<p>
510You won't have to edit this file for use with ALSA. After our <c>rc-update add
511alsasound boot</c>, our system will load the correct modules at startup.
512</p>
513
514<p>
515It's not necessary to add <c>snd-pcm-oss</c> or <c>snd-mixer-oss</c> in this
516file. Check the <uri link="http://www.djcj.org/LAU/guide/alsbook/faq1.html">this
517FAQ</uri> for more info.
518</p>
519
520</body>
521</section>
522<section>
523<title>Known bugs</title>
524<body>
525
526<note>
527This guide lags behind on the alsa-development. Chances are these bugs
528are already fixed when you read this.
529</note>
530 591
531<ul> 592<ul>
532 <li> 593 <li>
533 If you have <b>lots of noise</b> when using <b>oss</b> emulation, add 594 To move between channels, use your left and right arrow keys. (&lt;-
534 <e>options snd-pcm-oss dsp_map=1</e> to <path>/etc/modules.d/alsa</path> 595 &amp; -&gt;)
596 </li>
597 <li>
598 To toggle mute, move to the specific channel, for example Master and press
599 the <e>m</e> key on the keyboard.
600 </li>
601 <li>
602 To increase and decrease the volume levels, use the up and down arrow keys
603 respectively.
535 </li> 604 </li>
536</ul> 605</ul>
537 606
607<note>
608Be careful when setting your Bass and Treble values. 50 is usually a good
609number for both. Extremely high values of Bass may cause <e>jarring</e>
610on speakers that are not designed to handle them.
611</note>
612
613<p>
614After you're all done, your ALSA Mixer should look similar to the one below.
615Note the 00 instead of the MM and also the volume levels for some optimum
616settings.
617</p>
618
619<figure link="/images/docs/alsa-mixerunmuted.png" short="AlsaMixer Unmuted" caption="Alsa Mixer ready to roll"/>
620
538</body> 621</body>
539</section>
540<section> 622</section>
541<title>Activating Joystick Support</title>
542<body>
543
544<p>
545If your soundcard has a joystick plug, you might be interested in activating
546joystick support for your soundcard. If so, start by verifying if your soundcard
547driver has a joystick parameter. You can verify this by running <c>modinfo</c>
548against your <path>snd-&lt;your chipset&gt;</path>. For instance, for the
549<c>snd-via82xx</c>:
550</p>
551
552<pre caption="Running modinfo">
553# <i>modinfo snd-via82xx</i>
554filename: /lib/modules/2.4.22-ck2/snd-via82xx.o
555description: "VIA VT82xx audio"
556author: "Jaroslav Kysela &lt;perex@suse.cz&gt;"
557license: "GPL"
558parm: index int array (min = 1, max = 8), description "Index value for VIA 82xx bridge."
559parm: id string array (min = 1, max = 8), description "ID string for VIA 82xx bridge."
560parm: enable int array (min = 1, max = 8), description "Enable audio part of VIA 82xx bridge."
561parm: mpu_port long array (min = 1, max = 8), description "MPU-401 port. (VT82C686x only)"
562<i>parm: joystick int array (min = 1, max = 8), description "Enable joystick. (VT82C686x only)"</i>
563parm: ac97_clock int array (min = 1, max = 8), description "AC'97 codec clock (default 48000Hz)."
564parm: dxs_support int array (min = 1, max = 8), description "Support for DXS channels
565 (0 = auto, 1 = enable, 2 = disable, 3 = 48k only, 4 = no VRA)"
566</pre>
567
568<p>
569If it has the <c>joystick</c> parameter, then append <c>joystick=1</c> to your
570<c>options</c> line in <path>/etc/modules.d/alsa</path>. For instance, for the
571<c>snd-via82xx</c>:
572</p>
573
574<pre caption="Adding the joystick parameter">
575alias snd-card-0 snd-via82xx
576options snd-via82xx joystick=1
577</pre>
578
579</body>
580</section> 623<section>
624<title>Sound Check!</title>
625<body>
626
627<p>
628Finally. Some music. If everything above is perfect, you should now be able to
629listen to some good music. A quick way to test is to use a command line tool
630like <c>media-sound/madplay</c>. You could also use something more well known
631like <c>mpg123</c>. If you are an ogg fan, you could use <c>ogg123</c> provided
632by <c>media-sound/vorbis-tools</c>. Use any player you are comfortable with. As
633always, <c>emerge</c> what you need.
634</p>
635
636<pre caption="Getting the software">
637<comment>(Install the applications you want)</comment>
638# <i>emerge madplay mpg123</i>
639<comment>(To play .ogg files)</comment>
640# <i>emerge vorbis-tools</i>
641</pre>
642
643<p>
644And then play your favorite sound track...
645</p>
646
647<pre caption="Playing Music">
648# <i>madplay -v /mnt/shyam/Music/Paul\ Oakenfold\ -\ Dread\ Rock.mp3</i>
649MPEG Audio Decoder 0.15.2 (beta) - Copyright (C) 2000-2004 Robert Leslie et al.
650 Title: Dread Rock
651 Artist: Paul Oakenfold
652 Album: Matrix Reloaded
653 Year: 2003
654 Genre: Soundtrack
655 Soundtrack
656 00:04:19 Layer III, 160 kbps, 44100 Hz, joint stereo (MS), no CRC
657
658# <i>ogg123 Paul\ Oakenfold\ -\ Dread\ Rock.ogg</i>
659Audio Device: Advanced Linux Sound Architecture (ALSA) output
660
661Playing: Paul Oakenfold - Dread Rock.ogg
662Ogg Vorbis stream: 2 channel, 44100 Hz
663Genre: Soundtrack
664Transcoded: mp3;160
665Title: Dread Rock
666Artist: Paul Oakenfold
667Date: 2003
668Album: Matrix Reloaded
669Time: 00:11.31 [04:28.75] of 04:40.06 (200.6 kbps) Output Buffer 96.9%
670</pre>
671
672</body>
581<section> 673</section>
582<title>More links..</title> 674<section>
675<title>ALSA and USE</title>
676<body>
677
678<p>
679You can now add the <c>alsa</c> use flag to <path>/etc/make.conf</path> to
680ensure that your applications that support ALSA get built with it. Some
681architectures like x86 and amd64 have the flag enabled by default.
682</p>
683
583<body> 684</body>
685</section>
686<section>
687<title>Issues?</title>
688<body>
584 689
585<p>
586You could check these for additional info:
587</p> 690<p>
691If for some reason you're unable to hear sound, the first thing to do would
692be to check your <uri link="#doc_chap3_pre6">alsamixer</uri> settings. 80% of
693the issues lie with muted channels or low volume. Also check your Window
694Manager's sound applet and verify that volumes are set to audible levels.
695</p>
696
697<p>
698<path>/proc</path> is your friend. And in this case, <path>/proc/asound</path>
699is your best friend. We shall just take a short look at how much info is made
700available to us there.
701</p>
702
703<pre caption="Fun with /proc/asound">
704<comment>(First and foremost, if /proc/asound/cards shows your card, ALSA has
705picked up your sound card fine.)</comment>
706# <i>cat /proc/asound/cards</i>
7070 [Live ]: EMU10K1 - Sound Blaster Live!
708 Sound Blaster Live! (rev.6, serial:0x80271102) at 0xb800, irq 11
709
710<comment>(If you run ALSA off the kernel like I do and wonder how far behind
711you are from alsa-driver, this displays current running ALSA version)</comment>
712# <i>cat /proc/asound/version</i>
713Advanced Linux Sound Architecture Driver Version 1.0.8 (Thu Jan 13 09:39:32 2005 UTC).
714
715<comment>(ALSA OSS emulation details)</comment>
716# <i>cat /proc/asound/oss/sndstat</i>
717Sound Driver:3.8.1a-980706 (ALSA v1.0.8 emulation code)
718Kernel: Linux airwolf.zion 2.6.11ac1 #2 Wed May 4 00:35:08 IST 2005 i686
719Config options: 0
720
721Installed drivers:
722Type 10: ALSA emulation
723
724Card config:
725Sound Blaster Live! (rev.6, serial:0x80271102) at 0xb800, irq 11
726
727Audio devices:
7280: EMU10K1 (DUPLEX)
729
730Synth devices: NOT ENABLED IN CONFIG
731
732Midi devices:
7330: EMU10K1 MPU-401 (UART)
734
735Timers:
7367: system timer
737
738Mixers:
7390: SigmaTel STAC9721/23
740</pre>
741
742<p>
743The other most common issue users face is the dreaded "Unknown symbol in module"
744error. An example of the same is shown below.
745</p>
746
747<pre caption="Unknown Symbol in module error">
748# <i>/etc/init.d/alsasound start</i>
749 * Loading ALSA modules ...
750 * Loading: snd-card-0 ... [ ok ]
751 * Loading: snd-pcm-oss ...
752WARNING: Error inserting snd_mixer_oss
753(/lib/modules/2.6.12-gentoo-r6/kernel/sound/core/oss/snd-mixer-oss.ko): Unknown
754symbol in module, or unknown parameter (see dmesg) FATAL: Error inserting
755snd_pcm_oss
756(/lib/modules/2.6.12-gentoo-r6/kernel/sound/core/oss/snd-pcm-oss.ko): Unknown
757symbol in module, or unknown parameter (see dmesg)
758 [ !! ]
759 * Loading: snd-mixer-oss ...
760FATAL: Error inserting snd_mixer_oss
761(/lib/modules/2.6.12-gentoo-r6/kernel/sound/core/oss/snd-mixer-oss.ko): Unknown
762symbol in module, or unknown parameter (see dmesg)
763 [ !! ]
764 * Loading: snd-seq ... [ ok ]
765 * Loading: snd-emu10k1-synth ... [ ok ]
766 * Loading: snd-seq-midi ... [ ok ]
767 * Restoring Mixer Levels ... [ ok ]
768</pre>
769
770<p>
771And when you take a look at <c>dmesg</c> as suggested, you're quite likely to
772see:
773</p>
774
775<pre caption="dmesg output">
776<comment>(Only relevant portions are shown below)</comment>
777# <i>dmesg | less</i>
778ACPI: PCI Interrupt 0000:02:06.0[A] -> Link [APC3] -> GSI 18 (level, low) -> IRQ 209
779snd_mixer_oss: Unknown symbol snd_unregister_oss_device
780snd_mixer_oss: Unknown symbol snd_register_oss_device
781snd_mixer_oss: Unknown symbol snd_mixer_oss_notify_callback
782snd_mixer_oss: Unknown symbol snd_oss_info_register
783snd_pcm_oss: Unknown symbol snd_unregister_oss_device
784snd_pcm_oss: Unknown symbol snd_register_oss_device
785snd_pcm_oss: Unknown symbol snd_mixer_oss_ioctl_card
786snd_pcm_oss: Unknown symbol snd_oss_info_register
787snd_mixer_oss: Unknown symbol snd_unregister_oss_device
788snd_mixer_oss: Unknown symbol snd_register_oss_device
789snd_mixer_oss: Unknown symbol snd_mixer_oss_notify_callback
790snd_mixer_oss: Unknown symbol snd_oss_info_register
791</pre>
792
793<p>
794The above issue is caused when you switch from <c>alsa-driver</c> to in-kernel
795ALSA because when you unmerge <c>alsa-driver</c> the module files are config
796protected and hence get left behind. So, when you switch to in-kernel
797drivers, running <c>modprobe</c> gives you a mix of <c>alsa-driver</c> and
798in-kernel modules thus causing the above errors.
799</p>
800
801<p>
802The solution is quite easy. We just need to manually remove the problem causing
803directory after you unmerge <c>alsa-driver</c>. Be sure to remove the correct
804kernel version and not the current one!
805</p>
806
807<pre caption="Removing the alsa-driver modules">
808# <i>rm -rf /lib/modules/$(uname -r)/alsa-driver</i>
809</pre>
810
811<p>
812Another reason for error messages similar to the ones above could be a file in
813<path>/etc/modules.d</path> supplying a <c>device_mode</c> parameter when it
814isn't required. Confirm that this is indeed the issue and find out which file
815is the culprit.
816</p>
817
818<pre caption="Confirming and searching for device_mode">
819<comment>(Check dmesg to confirm)</comment>
820# <i>dmesg | grep device_mode</i>
821snd: Unknown parameter `device_mode'
822<comment>(Now, to get to the source of the issue)</comment>
823# <i>grep device_mode /etc/modules.d/*</i>
824</pre>
825
826<p>
827Usually it is a file called <path>alsa</path> with the line <c>options snd
828device_mode=0666</c>. Remove this line and restart the alsasound service and
829that should take care of this issue.
830</p>
831
832</body>
833</section>
834</chapter>
835
836<chapter>
837<title>Other things ALSA</title>
838<section id="midi">
839<title>Setting up MIDI support</title>
840<body>
841
842<p>
843First, check to make sure that you enabled the <c>midi</c> USE flag in
844<path>/etc/make.conf</path>. If you didn't, go ahead and add it now. You will
845also need to re-emerge any ALSA packages that use the <c>midi</c> flag, such as
846<c>alsa-lib</c>, <c>alsa-utils</c>, and <c>alsa-driver</c>.
847</p>
848
849<p>
850If your sound card is one of those that come with on-board MIDI synthesizers
851and you would like to listen to some .mid files, you have to install
852<c>awesfx</c> which is basically a set of utilities for controlling the AWE32
853driver. We need to install it first. If you don't have a hardware synthesizer,
854you can use a virtual one. Please see the section on
855<uri link="#vsynth">Virtual Synthesizers</uri> for more information.
856</p>
857
858<pre caption="Installing awesfx">
859# <i>emerge awesfx</i>
860</pre>
861
862<note>
863You will need to copy over SoundFont (SF2) files from your sound card's driver
864CD or a Windows installation into <path>/usr/share/sounds/sf2/</path>. For
865example a sound font file for the Creative SBLive! card would be 8MBGMSFX.SF2.
866</note>
867
868<p>
869After copying over the Soundfont files, we can then play a midi file as shown.
870You can also add the <c>asfxload</c> command to
871<path>/etc/conf.d/local.start</path>, so that the sound font is loaded
872every time the system starts up.
873</p>
874
875<note>
876<path>/mnt</path> paths mentioned in the code listing(s) below will <e>not</e>
877be the same in your machine. They are just an example. Please be careful to
878change the path to suit your machine.
879</note>
880
881<pre caption="Loading Soundfonts">
882<comment>(First, copy the Soundfont)</comment>
883# <i>cp /mnt/win2k/Program\ Files/CreativeSBLive2k/SFBank/8MBGMSFX.SF2 /usr/share/sounds/sf2/</i>
884<comment>(Or get it from your SoundBlaster CD)</comment>
885# <i>cp /mnt/cdrom/AUDIO/ENGLISH/SFBANK/8MBGMSFX.SF2 /usr/share/sounds/sf2/</i>
886<comment>(We load the specific Soundfont)</comment>
887# <i>asfxload /usr/share/sounds/sf2/8MBGMSFX.SF2</i>
888</pre>
889
890<p>
891You can now play midi files using a program like <c>aplaymidi</c>. Run
892<c>aplaymidi -l</c> to get a list of available ports and then pick one
893to play the file on.
894</p>
895
896<pre caption="Playing MIDI">
897<comment>(Check open ports)</comment>
898# <i>aplaymidi -l</i>
899 Port Client name Port name
900 64:0 EMU10K1 MPU-401 (UART) EMU10K1 MPU-401 (UART)
901 65:0 Emu10k1 WaveTable Emu10k1 Port 0
902 65:1 Emu10k1 WaveTable Emu10k1 Port 1
903 65:2 Emu10k1 WaveTable Emu10k1 Port 2
904 65:3 Emu10k1 WaveTable Emu10k1 Port 3
905<comment>(Pick a port, and play a mid file)</comment>
906# <i> aplaymidi --port=65:0 /mnt/shyam/music/midi/mi2.mid</i>
907</pre>
908
909</body>
910</section>
911<section id="vsynth">
912<title>Virtual Synthesizers</title>
913<body>
914
915<p>
916If your sound card lacks a hardware synthesizer, you could use a virtual one
917like <c>timidity++</c>. Installation is a breeze.
918</p>
919
920<pre caption="Installing timidity++">
921# <i>emerge timidity++</i>
922</pre>
923
924<p>
925For timidity to play sounds, it needs a sound font. Fortunately, the ebuild will
926install some sound font packages for you. There are a few other font packages
927available in Portage, such as <c>timidity-freepats</c> and
928<c>timidity-eawpatches</c>. You can have multiple sound font configurations
929installed, and you can place your own in <path>/usr/share/timidity/</path>. To
930switch between different timidity configurations, you should use
931<c>eselect</c>.
932</p>
933
934<pre caption="Changing configurations">
935# <i>eselect timidity list</i>
936# <i>eselect timidity set eawpatches</i>
937</pre>
938
939<p>
940Don't forget to add <c>timidity</c> to the default runlevel.
941</p>
942
943<pre caption="Adding timidity to the default runlevel">
944# <i>rc-update add timidity default</i>
945# <i>/etc/init.d/timidity start</i>
946</pre>
947
948<p>
949You can now try out <uri link="#doc_chap4_pre3">Playing MIDI</uri> files.
950</p>
951
952</body>
953</section>
954<section>
955<title>Tools and Firmware</title>
956<body>
957
958<p>
959Some specific sound cards can benefit from certain tools provided by the
960<c>alsa-tools</c> and <c>alsa-firmware</c> packages. You may install either with
961a simple <c>emerge</c>.
962</p>
963
964<pre caption="Installing ALSA Tools">
965# <i>emerge alsa-tools</i>
966</pre>
967
968</body>
969</section>
970<section>
971<title>Multiple sound cards</title>
972<body>
973
974<p>
975You can have more than one sound card in your system simultaneously, provided
976that you have built ALSA as modules in your kernel (or have installed
977<c>alsa-driver</c> instead). You just need to specify which should be started
978first in <path>/etc/modules.d/alsa</path>. Your cards are identified by their
979driver names inside this file. 0 is the first card, 1 is the second, and so on.
980Here's an example for a system with two sound cards.
981</p>
982
983<pre caption="Two sound cards in /etc/modules.d/alsa">
984options snd-emu10k1 index=0
985options snd-via82xx index=1
986</pre>
987
988<p>
989Or, if you have two cards that use the same driver, you specify them on the same
990line, using comma-separated numbers. Here's an example for a system with three
991sound cards, two of which are the same Intel High Definition Audio card.
992</p>
993
994<pre caption="Multiple sound cards in /etc/modules.d/alsa">
995options snd-ymfpci index=0
996options snd-hda-intel index=1,2
997</pre>
998
999</body>
1000</section>
1001<section>
1002<title>Plugins</title>
1003<body>
1004
1005<p>
1006You may want to install some plugins for extra functionality.
1007<c>alsa-plugins</c> is a collection of useful plugins, which include: PulseAudio
1008output, a sample rate converter, jack (a low-latency audio server), and an
1009encoder that lets you output 6-channel audio through digital S/PDIF connections
1010(both optical and coaxial). You can choose which of its plugins you want
1011installed by adding their USE flags to <path>/etc/portage/package.use</path>.
1012</p>
1013
1014<pre caption="Installing alsa-plugins">
1015# <i>emerge -avt alsa-plugins</i>
1016</pre>
1017
1018</body>
1019</section>
1020<section>
1021<title>A big thank you to...</title>
1022<body>
1023
1024<p>
1025Everyone who contributed to the earlier version of the Gentoo ALSA Guide:
1026Vincent Verleye, Grant Goodyear, Arcady Genkin, Jeremy Huddleston,
1027John P. Davis, Sven Vermeulen, Benny Chuang, Tiemo Kieft and Erwin.
1028</p>
1029
1030</body>
1031</section>
1032<section>
1033<title>References</title>
1034<body>
588 1035
589<ul> 1036<ul>
590 <li>
591 <uri link="http://www.gentoo.org/doc/en/desktop.xml">The Gentoo Linux
592 Desktop Configuration Guide</uri>
593 </li>
594 <li>
595 <uri link="http://www.alsa-project.org">ALSA Project Homepage</uri> 1037 <li><uri link="http://www.alsa-project.org/">The ALSA Project</uri></li>
596 </li>
597 <li>
598 <uri link="http://www.alsa-project.org/documentation.php3">ALSA Users
599 Documentation</uri>
600 </li>
601 <li>
602 <uri link="http://www.djcj.org">ALSA Howto's and FAQ's</uri>
603 </li>
604 <li>
605 <uri link="http://tldp.org/HOWTO/Sound-HOWTO/index.html">Linux Sound
606 HOWTO</uri>
607 </li>
608 <li>
609 <uri link="http://linux-sound.org/">Sound and MIDI Software For Linux</uri> 1038 <li><uri link="http://linux-sound.org">Linux Sound/MIDI Software</uri></li>
610 </li>
611</ul> 1039</ul>
612 1040
613</body> 1041</body>
614</section> 1042</section>
615</chapter> 1043</chapter>

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