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1 fox2mike 1.51 <?xml version='1.0' encoding="UTF-8"?>
2 nightmorph 1.80 <!-- $Header: /var/cvsroot/gentoo/xml/htdocs/doc/en/alsa-guide.xml,v 1.79 2007/05/07 07:08:24 nightmorph Exp $ -->
3 fox2mike 1.51
4 drobbins 1.1 <!DOCTYPE guide SYSTEM "/dtd/guide.dtd">
5    
6 cam 1.42 <guide link="/doc/en/alsa-guide.xml">
7 drobbins 1.1 <title>Gentoo Linux ALSA Guide</title>
8 fox2mike 1.51
9 swift 1.20 <author title="Author">
10 fox2mike 1.52 <mail link="fox2mike@gentoo.org">Shyam Mani</mail>
11 erwin 1.26 </author>
12 nightmorph 1.71 <author title="Author">
13     <mail link="nightmorph@gentoo.org">Joshua Saddler</mail>
14     </author>
15     <author title="Contributor">
16     <mail link="flameeyes@gentoo.org">Diego Pettenò</mail>
17     </author>
18 drobbins 1.1
19     <abstract>
20 fox2mike 1.51 This document helps a user setup ALSA on Gentoo Linux.
21 swift 1.20 </abstract>
22 drobbins 1.1
23 fox2mike 1.51 <!-- The content of this document is licensed under the CC-BY-SA license -->
24 fox2mike 1.54 <!-- See http://creativecommons.org/licenses/by-sa/2.5 -->
25 swift 1.25 <license/>
26    
27 nightmorph 1.79 <version>2.22</version>
28     <date>2007-05-07</date>
29 drobbins 1.1
30     <chapter>
31 fox2mike 1.51 <title>Introduction</title>
32 drobbins 1.1 <section>
33 swift 1.20 <title>What is ALSA?</title>
34 drobbins 1.1 <body>
35 swift 1.20
36 drobbins 1.1 <p>
37 nightmorph 1.80 ALSA, which stands for <e>Advanced Linux Sound Architecture</e>, provides
38     audio and MIDI (<e>Musical Instrument Digital Interface</e>) functionality to
39     the Linux operating system. ALSA is the default sound subsystem in the 2.6
40     kernel thereby replacing OSS (<e>Open Sound System</e>), which was used in the
41 fox2mike 1.51 2.4 kernels.
42 drobbins 1.1 </p>
43    
44     <p>
45 nightmorph 1.80 ALSA's main features include efficient support for all types of audio
46     interfaces ranging from consumer sound cards to professional sound
47     equipment, fully modularized drivers, SMP and thread safety, backward
48     compatibility with OSS and a user-space library <c>alsa-lib</c> to make
49 fox2mike 1.51 application development a breeze.
50     </p>
51    
52     </body>
53     </section>
54     <section>
55     <title>ALSA on Gentoo</title>
56     <body>
57    
58     <p>
59 nightmorph 1.80 One of Gentoo's main strengths lies in giving the user maximum control over
60     how a system is installed/configured. ALSA on Gentoo follows the same
61     principle. There are two ways you can get ALSA support up and running on your
62 fox2mike 1.51 system. We shall look at them in detail in the next chapter.
63 drobbins 1.1 </p>
64 swift 1.20
65 drobbins 1.1 </body>
66     </section>
67     </chapter>
68 fox2mike 1.51
69 drobbins 1.1 <chapter>
70 swift 1.35 <title>Installing ALSA</title>
71 drobbins 1.1 <section>
72 fox2mike 1.51 <title>Options</title>
73 swift 1.17 <body>
74    
75 fox2mike 1.51 <warn>
76 nightmorph 1.80 The methods shown below are mutually exclusive. You cannot have ALSA compiled
77 fox2mike 1.51 in your kernel and use <c>media-sound/alsa-driver</c>. It <e>will</e> fail.
78     </warn>
79    
80     <p>
81 nightmorph 1.79 The two options are:
82 fox2mike 1.51 </p>
83    
84     <ol>
85 nightmorph 1.77 <li>
86     Use ALSA provided by your kernel. This is the preferred/recommended method.
87     </li>
88 nightmorph 1.71 <li>Use Gentoo's <c>media-sound/alsa-driver</c> package.</li>
89 fox2mike 1.51 </ol>
90    
91 neysx 1.64 <p>
92 nightmorph 1.71 The in-kernel drivers and the <c>alsa-driver</c> package can vary a little; it's
93     possible that features and fixes found in one might not yet be incorporated into
94     the other. The upstream developers are aware of this, but the two drivers are
95     effectively separate branches of the ALSA project; they are not entirely
96     identical. You should be aware that they might function slightly differently, so
97     if one doesn't work for you, try the other! We shall take a peek into both
98     before finally deciding on one.
99 fox2mike 1.51 </p>
100    
101     <p>
102 nightmorph 1.80 If you were to use ALSA provided by the kernel, the following are the pros and
103 nightmorph 1.79 cons:
104 fox2mike 1.51 </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 nightmorph 1.71 <ti>
114     No need to emerge yet another package; drivers are integrated into kernel.
115     </ti>
116 fox2mike 1.51 </tr>
117     <tr>
118     <th>+</th>
119     <ti>One shot solution, no repeating emerges.</ti>
120     </tr>
121     <tr>
122     <th>-</th>
123 nightmorph 1.71 <ti>Might be a slightly different version than <c>alsa-driver</c>.</ti>
124 fox2mike 1.51 </tr>
125     </table>
126    
127 swift 1.17 <p>
128 nightmorph 1.77 And, if you were to use <c>alsa-driver</c>,
129 swift 1.17 </p>
130    
131 fox2mike 1.51 <table>
132     <tr>
133     <th>alsa-driver</th>
134     <th>Pros and Cons</th>
135     </tr>
136     <tr>
137     <th>+</th>
138 nightmorph 1.71 <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 fox2mike 1.51 </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 swift 1.17 </body>
155     </section>
156     <section>
157 fox2mike 1.51 <title>So...</title>
158 drobbins 1.1 <body>
159 swift 1.20
160 drobbins 1.1 <p>
161 nightmorph 1.71 The differences between <c>alsa-driver</c> and the in-kernel ALSA drivers are
162     quite subtle, as mentioned earlier. Since there are not any huge differences,
163 nightmorph 1.77 you are encouraged to go through the process of using the ALSA provided by the
164     kernel <e>first</e> for ease of use. Before reporting any sound related issues
165     to <uri link="https://bugs.gentoo.org">Gentoo Bugzilla</uri>, please try to
166     reproduce them using <c>alsa-driver</c> and file the bug report no matter what
167     the result.
168 drobbins 1.1 </p>
169 swift 1.20
170 fox2mike 1.51 </body>
171     </section>
172     <section id="lspci">
173     <title>Before you proceed</title>
174     <body>
175 swift 1.20
176     <p>
177 nightmorph 1.80 Whichever method of install you choose, you need to know what drivers your
178 fox2mike 1.54 sound card uses. In most cases, sound cards (onboard and otherwise) are PCI
179 nightmorph 1.80 based and <c>lspci</c> will help you in digging out the required information.
180 fox2mike 1.54 Please <c>emerge sys-apps/pciutils</c> to get <c>lspci</c>, if you don't have it
181     installed 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
184 nightmorph 1.80 with ISA based sound cards:
185 fox2mike 1.54 </p>
186    
187     <ul>
188     <li>
189     <uri link="http://www.roestock.demon.co.uk/isapnptools/">The ISAPNPTOOLS
190     Page</uri>
191     </li>
192     <li>
193     <uri link="http://www2.linuxjournal.com/article/3269">LinuxJournal PnP
194     Article</uri>
195     </li>
196     <li>
197     <uri link="http://www.tldp.org/HOWTO/Sound-HOWTO/x320.html">TLDP Sound
198     HowTo</uri>
199     </li>
200     </ul>
201    
202     <note>
203     For ease of use/explanation, we assume the user has a PCI based sound card for
204     the remainder of this guide.
205     </note>
206    
207     <p>
208     We now proceed to find out details about the sound card.
209 drobbins 1.1 </p>
210 swift 1.20
211 fox2mike 1.51 <pre caption="Soundcard Details">
212     # <i>lspci -v | grep -i audio</i>
213     0000:00:0a.0 Multimedia audio controller: Creative Labs SB Live! EMU10k1 (rev 06)
214 drobbins 1.1 </pre>
215 swift 1.20
216 drobbins 1.1 <p>
217 nightmorph 1.78 We now know that the sound card on the machine is a Sound Blaster Live! and the
218     card manufacturer is Creative Labs. Head over to the <uri
219     link="http://bugtrack.alsa-project.org/main/index.php/Matrix:Main">ALSA
220 nightmorph 1.80 Soundcard Matrix</uri> page and select Creative Labs from the list. You will
221     be taken to the Creative Labs matrix page where you can see that the SB Live!
222     uses the <c>emu10k1</c> module. That is the information we need for now. If
223     you are interested in detailed information, you can click on the link next to
224 nightmorph 1.78 the "Details" and that will take you to the <c>emu10k1</c> specific page.
225 drobbins 1.1 </p>
226 swift 1.20
227 nightmorph 1.71 <p>
228     If 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
230     guide, we will show you how to set up <uri link="#midi">MIDI support</uri>.
231     </p>
232    
233 fox2mike 1.51 </body>
234     </section>
235     <section id="kernel">
236     <title>Using ALSA provided by your Kernel</title>
237     <body>
238    
239 swift 1.35 <p>
240 nightmorph 1.79 If you're a person who likes to keep things simple, then this is the way to go.
241 swift 1.35 </p>
242 swift 1.20
243 fox2mike 1.51 <note>
244 nightmorph 1.79 Since the 2005.0 release, Gentoo Linux uses 2.6 as the default kernel. Please
245     check that your kernel is a 2.6 series kernel. This method will <e>not</e> work
246     on a 2.4 kernel.
247 fox2mike 1.51 </note>
248    
249     <p>
250     Let us now configure the kernel to enable ALSA.
251     </p>
252    
253 fox2mike 1.54 <impo>
254 fox2mike 1.63 <c>genkernel</c> users should now run <c>genkernel --menuconfig all</c> and
255     then follow the instructions in <uri link="#doc_chap2_pre3">Kernel Options for
256     ALSA</uri>.
257 fox2mike 1.54 </impo>
258    
259 fox2mike 1.51 <pre caption="Heading over to the source">
260     # <i>cd /usr/src/linux</i>
261     # <i>make menuconfig</i>
262 erwin 1.26 </pre>
263    
264 fox2mike 1.51 <note>
265     The above example assumes that <path>/usr/src/linux</path> symlink points to
266     the kernel sources you want to use. Please ensure the same before proceeding.
267     </note>
268 neysx 1.46
269 erwin 1.26 <p>
270 fox2mike 1.51 Now we will look at some of the options we will have to enable in the 2.6
271     kernel to ensure proper ALSA support for our sound card.
272 erwin 1.26 </p>
273    
274 fox2mike 1.54 <p>
275 nightmorph 1.80 Please note that for ease of use, all examples show ALSA built as modules. It
276 nightmorph 1.71 is advisable to follow the same as it then allows the use of <c>alsaconf</c>
277 fox2mike 1.63 which is a boon when you want to configure your card. Please do <e>not</e> skip
278     the <uri link="#alsa-config">Configuration</uri> section of this document. If
279     you still like to have options built-in, ensure that you make changes to your
280     config accordingly.
281 fox2mike 1.54 </p>
282 fox2mike 1.51
283     <pre caption="Kernel Options for ALSA">
284     Device Drivers ---&gt;
285     Sound ---&gt;
286    
287     <comment>(This needs to be enabled)</comment>
288     &lt;M&gt; Sound card support
289    
290     <comment>(Make sure OSS is disabled)</comment>
291     Open Sound System ---&gt;
292     &lt; &gt; Open Sound System (DEPRECATED)
293    
294     <comment>(Move one step back and enter ALSA)</comment>
295     Advanced Linux Sound Architecture ---&gt;
296     &lt;M&gt; Advanced Linux Sound Architecture
297     <comment>(Select this if you want MIDI sequencing and routing)</comment>
298     &lt;M&gt; Sequencer support
299     <comment>(Old style /dev/mixer* and /dev/dsp* support. Recommended.)</comment>
300     &lt;M&gt; OSS Mixer API
301     &lt;M&gt; OSS PCM (digital audio) API
302    
303     <comment>(You now have a choice of devices to enable support for. Generally,
304 nightmorph 1.80 you will have one type of device and not more. If you have more than one
305 fox2mike 1.51 sound card, please enable them all here.)</comment>
306    
307 nightmorph 1.80 <comment>(Mostly for testing and development purposes, not needed for normal
308 fox2mike 1.51 users unless you know what you are doing.)</comment>
309     Generic devices ---&gt;
310    
311     <comment>(For ISA Sound cards)</comment>
312     ISA devices ---&gt;
313     <comment>(IF you had the Gravis, you would select this option)</comment>
314     &lt;M&gt; Gravis UltraSound Extreme
315    
316 nightmorph 1.80 <comment>(Move one level back and into PCI devices. Most sound cards today are
317 fox2mike 1.51 PCI devices)</comment>
318     PCI devices ---&gt;
319     <comment>(We now select the emu10k1 driver for our card)</comment>
320     &lt;M&gt; Emu10k1 (SB Live!, Audigy, E-mu APS)
321     <comment>(Or an Intel card would be)</comment>
322     &lt;M&gt; Intel/SiS/nVidia/AMD/ALi AC97 Controller
323     <comment>(Or if you have a VIA Card)</comment>
324     &lt;M&gt; VIA 82C686A/B, 8233/8235 AC97 Controller
325    
326     <comment>(Move one level back and select in case you have an USB sound card)</comment>
327     USB Devices ---&gt;
328 swift 1.35 </pre>
329 swift 1.20
330 fox2mike 1.51 <p>
331     Now that your options are set, you can (re)compile the kernel and ALSA support
332 swift 1.62 for your card should be functional once you reboot into the new kernel. Don't
333     forget to update your GRUB configuration to use the newly built kernel.
334 nightmorph 1.80 You can now proceed to <uri link="#alsa-utilities">ALSA Utilities</uri> and
335 fox2mike 1.51 see if everything is working as it should.
336     </p>
337 swift 1.20
338 drobbins 1.1 </body>
339     </section>
340 fox2mike 1.51 <section id="alsa-driver">
341     <title>Using the ALSA Driver package</title>
342 drobbins 1.1 <body>
343    
344     <p>
345 nightmorph 1.80 So you've decided to go the <c>alsa-driver</c> way. Let's get started then.
346     There are a few minor things to be done to ensure only the drivers for your
347     sound card are compiled. Although this is not really necessary, it cuts down
348 fox2mike 1.51 on the unnecessary drivers that will be compiled otherwise.
349 drobbins 1.1 </p>
350 swift 1.20
351 fox2mike 1.51 <p>
352 nightmorph 1.80 If you don't have an idea of what drivers your sound card might need, please
353     take a look at the <uri link="#lspci">lspci</uri> section of this guide. Once
354     you have your driver name (<c>emu10k1</c> in our example), edit
355 fox2mike 1.51 <path>/etc/make.conf</path> and add a variable, <c>ALSA_CARDS</c>.
356     </p>
357    
358     <pre caption="Adding ALSA_CARDS to make.conf">
359     <comment>(For one sound card)</comment>
360     ALSA_CARDS="emu10k1"
361 vanquirius 1.59 <comment>(For more than one, separate names with spaces)</comment>
362 fox2mike 1.51 ALSA_CARDS="emu10k1 via82xx"
363 blubber 1.16 </pre>
364    
365 drobbins 1.1 <p>
366 nightmorph 1.80 If you have compiled your kernel and want to use <c>alsa-driver</c>, please
367     ensure the following before proceeding, else <c>alsa-driver</c> is likely to
368 fox2mike 1.51 fail. The next code listing gives you one way of performing the checks.
369 drobbins 1.1 </p>
370 swift 1.20
371 fox2mike 1.54 <note>
372     <c>genkernel</c> users can proceed with <uri link="#doc_chap2_pre6">Installing
373     alsa-driver</uri> as their configuration is in sync with the one shown below by
374     default.
375     </note>
376    
377 fox2mike 1.51 <ol>
378     <li>
379     <c>CONFIG_SOUND</c> is set. (Basic Sound support enabled)
380     </li>
381     <li>
382     <c>CONFIG_SOUND_PRIME</c> is not set. (In-built OSS support disabled)
383     </li>
384     <li>
385     <c>CONFIG_SND</c> is not set. (In-built ALSA support disabled)
386     </li>
387     <li>
388     <path>/usr/src/linux</path> points to the kernel you want ALSA working on.
389     </li>
390     </ol>
391    
392     <pre caption=".config checks">
393     <comment>(Assuming the linux symlink points to the correct kernel)</comment>
394     # <i>cd /usr/src/linux</i>
395     # <i>grep SOUND .config</i>
396     <comment>(1. is true)</comment>
397     CONFIG_SOUND=y
398     <comment>(2. is true)</comment>
399     CONFIG_SOUND_PRIME is not set
400     # <i>grep SND .config</i>
401     <comment>(and 3. is true)</comment>
402     CONFIG_SND is not set
403 drobbins 1.1 </pre>
404 swift 1.20
405 drobbins 1.1 <p>
406 fox2mike 1.54 Now all you have to do is type the magic words... and no, it's not abracadabra.
407 drobbins 1.1 </p>
408 swift 1.20
409 fox2mike 1.51 <pre caption="Installing alsa-driver">
410     # <i>emerge alsa-driver</i>
411     </pre>
412    
413     <impo>
414 nightmorph 1.71 Please note that you will have to run <c>emerge alsa-driver</c> after every
415     kernel (re)compile, as the earlier drivers are deleted. To make this task
416     easier, you may want to emerge the <c>module-rebuild</c> package, which will
417 nightmorph 1.72 keep track of module packages and rebuild them for you. First run
418     <c>module-rebuild populate</c> to create the list, and then after every kernel
419 nightmorph 1.71 (re)compile, you just run <c>module-rebuild rebuild</c>, and your external
420     modules will be rebuilt.
421 fox2mike 1.51 </impo>
422    
423 drobbins 1.1 </body>
424     </section>
425 swift 1.35 </chapter>
426 fox2mike 1.51
427 swift 1.35 <chapter>
428 fox2mike 1.51 <title>Configuring/Testing ALSA</title>
429     <section id="alsa-utilities">
430     <title>ALSA Utilities</title>
431 drobbins 1.1 <body>
432 swift 1.20
433 drobbins 1.1 <p>
434 nightmorph 1.80 <c>alsa-utils</c> forms an integral part of ALSA as it has a truckload of
435     programs that are highly useful, including the ALSA Initscripts. Hence we
436 fox2mike 1.51 strongly recommend that you install <c>alsa-utils</c>
437 drobbins 1.1 </p>
438 swift 1.12
439 fox2mike 1.51 <pre caption="Install alsa-utils">
440     # <i>emerge alsa-utils</i>
441 drobbins 1.1 </pre>
442 swift 1.20
443 fox2mike 1.51 <note>
444 nightmorph 1.80 If you activated ALSA in your <uri link="#kernel">kernel</uri> <e>and</e> did
445     not compile ALSA as modules, please proceed to the
446     <uri link="#initscript">ALSA Initscript</uri> section. The rest of you need
447     to configure ALSA. This is made very easy by the existence of the
448 fox2mike 1.51 <c>alsaconf</c> tool provided by <c>alsa-utils</c>.
449     </note>
450    
451     </body>
452     </section>
453     <section id="alsa-config">
454     <title>Configuration</title>
455     <body>
456    
457 nightmorph 1.71 <p>
458     Recent versions of <c>udev</c> (<c>>=udev-103</c>) provide some degree of
459     kernel-level autoconfiguration of your sound card. If possible, try to rely on
460     just letting your kernel automatically setup your sound card for you. Otherwise,
461     use <c>alsaconf</c> to configure your card, as shown below.
462     </p>
463    
464 fox2mike 1.51 <note>
465 nightmorph 1.80 Please shut down any programs that <e>might</e> access the sound card while
466 fox2mike 1.51 running <c>alsaconf</c>.
467     </note>
468    
469 drobbins 1.1 <p>
470 nightmorph 1.80 To configure your sound card just type <c>alsaconf</c> in a shell as root.
471 swift 1.20 </p>
472    
473 fox2mike 1.51 <pre caption="Invoking alsaconf">
474     # <i>alsaconf</i>
475 drobbins 1.1 </pre>
476 swift 1.20
477 fox2mike 1.51 <p>
478 nightmorph 1.80 You will now see a neat menu guided interface that will automatically probe
479     your devices and try to find out your sound card. You will be asked to pick
480     your sound card from a list. Once that's done, it will ask you permission to
481     automatically make required changes to <path>/etc/modules.d/alsa</path>.
482 fox2mike 1.54 It will then adjust your volume settings to optimum levels, run
483 nightmorph 1.76 <c>update-modules</c> and start the <path>/etc/init.d/alsasound</path> service.
484 fox2mike 1.63 Once <c>alsaconf</c> exits, you can proceed with setting up the ALSA
485     initscript.
486 fox2mike 1.51 </p>
487    
488 swift 1.35 </body>
489     </section>
490 fox2mike 1.51 <section id="initscript">
491     <title>ALSA Initscript</title>
492 swift 1.35 <body>
493 swift 1.20
494 drobbins 1.1 <p>
495 nightmorph 1.80 We're now almost all setup. Whichever method you chose to install ALSA, you'll
496     need to have something load your modules or initialize ALSA and restore your
497     volume settings when your system comes up. The ALSA Initscript handles all of
498 neysx 1.56 this for you and is called <c>alsasound</c>. Add it to the boot runlevel.
499 drobbins 1.1 </p>
500 swift 1.20
501 neysx 1.56 <pre caption="Adding ALSA to the boot runlevel">
502 fox2mike 1.54 # <i>rc-update add alsasound boot</i>
503     * alsasound added to runlevel boot
504 fox2mike 1.51 * rc-update complete.
505 drobbins 1.1 </pre>
506 swift 1.20
507 fox2mike 1.51 <p>
508 nightmorph 1.80 Next, just check the <path>/etc/conf.d/alsasound</path> file and ensure that
509     SAVE_ON_STOP variable is set to yes. This saves your sound settings when you
510 fox2mike 1.51 shutdown your system.
511     </p>
512    
513 drobbins 1.1 </body>
514     </section>
515     <section>
516 fox2mike 1.54 <title>Audio Group</title>
517     <body>
518    
519     <p>
520     Before we move on to testing, there's one last <e>important</e> thing that needs
521 nightmorph 1.79 to be setup. Rule of thumb in a *nix OS: Do not run as root unless needed.
522 fox2mike 1.54 This applies here as well ;) How? Well, most of the times you should be logged
523     in as a user and would like to listen to music or access your soundcard. For
524 vanquirius 1.59 that to happen, you need to be in the "audio" group. At this point, we'll add
525 fox2mike 1.54 users to the audio group, so that they won't have any issues when they want to
526     access sound devices. We'll use <c>gpasswd</c> here and you need to be logged in
527     as root for this to work.
528     </p>
529    
530     <pre caption="Adding users to the audio group">
531     <comment>(Substitute &lt;username&gt; with your user)</comment>
532     # <i>gpasswd -a &lt;username&gt; audio </i>
533     Adding user &lt;username&gt; to group audio
534     </pre>
535    
536     </body>
537     </section>
538     <section>
539 fox2mike 1.51 <title>Volume Check!</title>
540 drobbins 1.1 <body>
541 swift 1.20
542 drobbins 1.1 <p>
543 nightmorph 1.80 We've completed all the setups and prerequisites, so let's fire up ALSA. If
544     you ran <c>alsaconf</c>, you can skip this step, since <c>alsaconf</c> already
545 fox2mike 1.51 does this for you.
546 swift 1.20 </p>
547    
548 fox2mike 1.51 <pre caption="Start the service">
549 nightmorph 1.80 # <i>/etc/init.d/alsasound start</i>
550 fox2mike 1.51 </pre>
551    
552     <p>
553 nightmorph 1.80 Now that the required things have been taken care of, we need to check up on
554 fox2mike 1.54 the volume as in certain cases, it is muted. We use <c>alsamixer</c> for this
555     purpose.
556 fox2mike 1.51 </p>
557    
558     <pre caption="Starting alsamixer">
559     <comment>(Opens up a console program. Only required settings are shown)</comment>
560     # <i>alsamixer</i>
561 drobbins 1.1 </pre>
562 swift 1.20
563 fox2mike 1.54 <impo>
564     If you have issues starting up <c>alsamixer</c> and get errors such as
565     alsamixer: function snd_ctl_open failed for default: No such file or directory,
566 alin 1.58 this is usually an issue with udev setting up the devices. Run <c>killall
567     udevd; udevstart</c> to reload <path>/dev</path> entries and fire up
568     <c>alsamixer</c>. It should solve the issue.
569 fox2mike 1.54 </impo>
570    
571 fox2mike 1.51 <p>
572 nightmorph 1.80 This is how the ALSA Mixer <e>might</e> look the first time you open it. Pay
573     attention to the Master and PCM channels which both have an MM below them.
574     That means they are muted. If you try to play anything with <c>alsamixer</c>
575 fox2mike 1.51 in this state, you will not hear anything on your speakers.
576     </p>
577    
578     <figure link="/images/docs/alsa-mixermuted.png" short="AlsaMixer Muted" caption="The Alsa Mixer Main Window, Muted"/>
579    
580     <p>
581     Now, we shall unmute the channels, and set volume levels as needed.
582     </p>
583    
584     <warn>
585 fox2mike 1.54 Both Master <e>and</e> PCM need to be unmuted and set to audible volume levels
586     if you want to hear some output on your speakers.
587 fox2mike 1.51 </warn>
588    
589     <ul>
590     <li>
591 nightmorph 1.80 To move between channels, use your left and right arrow keys. (&lt;-
592 fox2mike 1.51 &amp; -&gt;)
593     </li>
594     <li>
595 nightmorph 1.80 To toggle mute, move to the specific channel, for example Master and press
596     the <e>m</e> key on the keyboard.
597 fox2mike 1.51 </li>
598     <li>
599 nightmorph 1.80 To increase and decrease the volume levels, use the up and down arrow keys
600 fox2mike 1.51 respectively.
601     </li>
602     </ul>
603    
604     <note>
605 nightmorph 1.80 Be careful when setting your Bass and Treble values. 50 is usually a good
606     number for both. Extremely high values of Bass may cause <e>jarring</e>
607 fox2mike 1.51 on speakers that are not designed to handle them.
608     </note>
609    
610     <p>
611 nightmorph 1.80 After you're all done, your ALSA Mixer should look similar to the one below.
612     Note the 00 instead of the MM and also the volume levels for some optimum
613 fox2mike 1.51 settings.
614     </p>
615    
616     <figure link="/images/docs/alsa-mixerunmuted.png" short="AlsaMixer Unmuted" caption="Alsa Mixer ready to roll"/>
617    
618 drobbins 1.1 </body>
619     </section>
620     <section>
621 fox2mike 1.51 <title>Sound Check!</title>
622 drobbins 1.1 <body>
623 swift 1.20
624 drobbins 1.1 <p>
625 fox2mike 1.54 Finally. Some music. If everything above is perfect, you should now be able to
626     listen to some good music. A quick way to test is to use a command line tool
627     like <c>media-sound/madplay</c>. You could also use something more well known
628 nightmorph 1.70 like <c>mpg123</c>. If you are an ogg fan, you could use <c>ogg123</c> provided
629     by <c>media-sound/vorbis-tools</c>. Use any player you are comfortable with. As
630     always, <c>emerge</c> what you need.
631 fox2mike 1.51 </p>
632    
633     <pre caption="Getting the software">
634     <comment>(Install the applications you want)</comment>
635 nightmorph 1.70 # <i>emerge madplay mpg123</i>
636 fox2mike 1.51 <comment>(To play .ogg files)</comment>
637     # <i>emerge vorbis-tools</i>
638     </pre>
639    
640     <p>
641     And then play your favorite sound track...
642 drobbins 1.1 </p>
643 swift 1.20
644 fox2mike 1.51 <pre caption="Playing Music">
645     # <i>madplay -v /mnt/shyam/Music/Paul\ Oakenfold\ -\ Dread\ Rock.mp3</i>
646     MPEG Audio Decoder 0.15.2 (beta) - Copyright (C) 2000-2004 Robert Leslie et al.
647     Title: Dread Rock
648     Artist: Paul Oakenfold
649     Album: Matrix Reloaded
650     Year: 2003
651     Genre: Soundtrack
652     Soundtrack
653     00:04:19 Layer III, 160 kbps, 44100 Hz, joint stereo (MS), no CRC
654    
655     # <i>ogg123 Paul\ Oakenfold\ -\ Dread\ Rock.ogg</i>
656     Audio Device: Advanced Linux Sound Architecture (ALSA) output
657    
658     Playing: Paul Oakenfold - Dread Rock.ogg
659     Ogg Vorbis stream: 2 channel, 44100 Hz
660     Genre: Soundtrack
661     Transcoded: mp3;160
662     Title: Dread Rock
663     Artist: Paul Oakenfold
664     Date: 2003
665     Album: Matrix Reloaded
666     Time: 00:11.31 [04:28.75] of 04:40.06 (200.6 kbps) Output Buffer 96.9%
667 drobbins 1.1 </pre>
668 swift 1.20
669 fox2mike 1.51 </body>
670     </section>
671     <section>
672 vanquirius 1.59 <title>ALSA and USE</title>
673 fox2mike 1.54 <body>
674    
675     <p>
676     You can now add the <c>alsa</c> use flag to <path>/etc/make.conf</path> to
677     ensure that your applications that support ALSA get built with it. Some
678     architectures like x86 and amd64 have the flag enabled by default.
679     </p>
680    
681     </body>
682     </section>
683     <section>
684 fox2mike 1.51 <title>Issues?</title>
685     <body>
686    
687 drobbins 1.1 <p>
688 nightmorph 1.80 If for some reason you're unable to hear sound, the first thing to do would
689     be to check your <uri link="#doc_chap3_pre6">alsamixer</uri> settings. 80% of
690     the issues lie with muted channels or low volume. Also check your Window
691 fox2mike 1.51 Manager's sound applet and verify that volumes are set to audible levels.
692 drobbins 1.1 </p>
693 swift 1.20
694 drobbins 1.1 <p>
695 nightmorph 1.80 <path>/proc</path> is your friend. And in this case, <path>/proc/asound</path>
696     is your best friend. We shall just take a short look at how much info is made
697 fox2mike 1.51 available to us there.
698 drobbins 1.1 </p>
699 swift 1.20
700 fox2mike 1.51 <pre caption="Fun with /proc/asound">
701 nightmorph 1.80 <comment>(First and foremost, if /proc/asound/cards shows your card, ALSA has
702 fox2mike 1.51 picked up your sound card fine.)</comment>
703     # <i>cat /proc/asound/cards</i>
704     0 [Live ]: EMU10K1 - Sound Blaster Live!
705     Sound Blaster Live! (rev.6, serial:0x80271102) at 0xb800, irq 11
706    
707 nightmorph 1.79 <comment>(This displays the current running ALSA version)</comment>
708 fox2mike 1.51 # <i>cat /proc/asound/version</i>
709     Advanced Linux Sound Architecture Driver Version 1.0.8 (Thu Jan 13 09:39:32 2005 UTC).
710 cam 1.47
711 fox2mike 1.51 <comment>(ALSA OSS emulation details)</comment>
712     # <i>cat /proc/asound/oss/sndstat</i>
713     Sound Driver:3.8.1a-980706 (ALSA v1.0.8 emulation code)
714     Kernel: Linux airwolf.zion 2.6.11ac1 #2 Wed May 4 00:35:08 IST 2005 i686
715     Config options: 0
716    
717     Installed drivers:
718     Type 10: ALSA emulation
719    
720     Card config:
721     Sound Blaster Live! (rev.6, serial:0x80271102) at 0xb800, irq 11
722    
723     Audio devices:
724     0: EMU10K1 (DUPLEX)
725 neysx 1.46
726 fox2mike 1.51 Synth devices: NOT ENABLED IN CONFIG
727 neysx 1.46
728 fox2mike 1.51 Midi devices:
729     0: EMU10K1 MPU-401 (UART)
730 swift 1.20
731 fox2mike 1.51 Timers:
732     7: system timer
733 neysx 1.46
734 fox2mike 1.51 Mixers:
735     0: SigmaTel STAC9721/23
736     </pre>
737 swift 1.20
738 fox2mike 1.61 <p>
739     The other most common issue users face is the dreaded "Unknown symbol in module"
740     error. An example of the same is shown below.
741     </p>
742    
743     <pre caption="Unknown Symbol in module error">
744     # <i>/etc/init.d/alsasound start</i>
745     * Loading ALSA modules ...
746     * Loading: snd-card-0 ... [ ok ]
747     * Loading: snd-pcm-oss ...
748     WARNING: Error inserting snd_mixer_oss
749     (/lib/modules/2.6.12-gentoo-r6/kernel/sound/core/oss/snd-mixer-oss.ko): Unknown
750     symbol in module, or unknown parameter (see dmesg) FATAL: Error inserting
751     snd_pcm_oss
752     (/lib/modules/2.6.12-gentoo-r6/kernel/sound/core/oss/snd-pcm-oss.ko): Unknown
753     symbol in module, or unknown parameter (see dmesg)
754     [ !! ]
755     * Loading: snd-mixer-oss ...
756     FATAL: Error inserting snd_mixer_oss
757     (/lib/modules/2.6.12-gentoo-r6/kernel/sound/core/oss/snd-mixer-oss.ko): Unknown
758     symbol in module, or unknown parameter (see dmesg)
759     [ !! ]
760     * Loading: snd-seq ... [ ok ]
761     * Loading: snd-emu10k1-synth ... [ ok ]
762     * Loading: snd-seq-midi ... [ ok ]
763     * Restoring Mixer Levels ... [ ok ]
764     </pre>
765    
766     <p>
767     And when you take a look at <c>dmesg</c> as suggested, you're quite likely to
768     see:
769     </p>
770    
771     <pre caption="dmesg output">
772     <comment>(Only relevant portions are shown below)</comment>
773     # <i>dmesg | less</i>
774     ACPI: PCI Interrupt 0000:02:06.0[A] -> Link [APC3] -> GSI 18 (level, low) -> IRQ 209
775     snd_mixer_oss: Unknown symbol snd_unregister_oss_device
776     snd_mixer_oss: Unknown symbol snd_register_oss_device
777     snd_mixer_oss: Unknown symbol snd_mixer_oss_notify_callback
778     snd_mixer_oss: Unknown symbol snd_oss_info_register
779     snd_pcm_oss: Unknown symbol snd_unregister_oss_device
780     snd_pcm_oss: Unknown symbol snd_register_oss_device
781     snd_pcm_oss: Unknown symbol snd_mixer_oss_ioctl_card
782     snd_pcm_oss: Unknown symbol snd_oss_info_register
783     snd_mixer_oss: Unknown symbol snd_unregister_oss_device
784     snd_mixer_oss: Unknown symbol snd_register_oss_device
785     snd_mixer_oss: Unknown symbol snd_mixer_oss_notify_callback
786     snd_mixer_oss: Unknown symbol snd_oss_info_register
787     </pre>
788    
789     <p>
790     The above issue is caused when you switch from <c>alsa-driver</c> to in-kernel
791     ALSA because when you unmerge <c>alsa-driver</c> the module files are config
792     protected and hence get left behind. So, when you switch to in-kernel
793     drivers, running <c>modprobe</c> gives you a mix of <c>alsa-driver</c> and
794     in-kernel modules thus causing the above errors.
795     </p>
796    
797     <p>
798     The solution is quite easy. We just need to manually remove the problem causing
799     directory after you unmerge <c>alsa-driver</c>. Be sure to remove the correct
800     kernel version and not the current one!
801     </p>
802    
803     <pre caption="Removing the alsa-driver modules">
804 rane 1.68 # <i>rm -rf /lib/modules/$(uname -r)/alsa-driver</i>
805 fox2mike 1.61 </pre>
806    
807 fox2mike 1.66 <p>
808     Another reason for error messages similar to the ones above could be a file in
809 neysx 1.67 <path>/etc/modules.d</path> supplying a <c>device_mode</c> parameter when it
810 fox2mike 1.66 isn't required. Confirm that this is indeed the issue and find out which file
811     is the culprit.
812     </p>
813    
814 neysx 1.67 <pre caption="Confirming and searching for device_mode">
815 fox2mike 1.66 <comment>(Check dmesg to confirm)</comment>
816     # <i>dmesg | grep device_mode</i>
817     snd: Unknown parameter `device_mode'
818     <comment>(Now, to get to the source of the issue)</comment>
819     # <i>grep device_mode /etc/modules.d/*</i>
820     </pre>
821    
822     <p>
823     Usually it is a file called <path>alsa</path> with the line <c>options snd
824     device_mode=0666</c>. Remove this line and restart the alsasound service and
825     that should take care of this issue.
826     </p>
827    
828 erwin 1.26 </body>
829     </section>
830     </chapter>
831 fox2mike 1.51
832 erwin 1.26 <chapter>
833 fox2mike 1.51 <title>Other things ALSA</title>
834 nightmorph 1.71 <section id="midi">
835 fox2mike 1.51 <title>Setting up MIDI support</title>
836 erwin 1.26 <body>
837    
838     <p>
839 nightmorph 1.71 First, check to make sure that you enabled the <c>midi</c> USE flag in
840 jkt 1.75 <path>/etc/make.conf</path>. If you didn't, go ahead and add it now. You will
841     also need to re-emerge any ALSA packages that use the <c>midi</c> flag, such as
842     <c>alsa-lib</c>, <c>alsa-utils</c>, and <c>alsa-driver</c>.
843 nightmorph 1.71 </p>
844    
845     <p>
846 nightmorph 1.80 If your sound card is one of those that come with on-board MIDI synthesizers
847     and you would like to listen to some .mid files, you have to install
848     <c>awesfx</c> which is basically a set of utilities for controlling the AWE32
849     driver. We need to install it first. If you don't have a hardware synthesizer,
850     you can use a virtual one. Please see the section on
851 fox2mike 1.51 <uri link="#vsynth">Virtual Synthesizers</uri> for more information.
852 erwin 1.26 </p>
853    
854 fox2mike 1.51 <pre caption="Installing awesfx">
855 erwin 1.26 # <i>emerge awesfx</i>
856     </pre>
857    
858 fox2mike 1.51 <note>
859 nightmorph 1.80 You will need to copy over SoundFont (SF2) files from your sound card's driver
860     CD or a Windows installation into <path>/usr/share/sounds/sf2/</path>. For
861 fox2mike 1.51 example a sound font file for the Creative SBLive! card would be 8MBGMSFX.SF2.
862     </note>
863    
864 erwin 1.26 <p>
865 fox2mike 1.51 After copying over the Soundfont files, we can then play a midi file as shown.
866 nightmorph 1.80 You can also add the <c>asfxload</c> command to
867     <path>/etc/conf.d/local.start</path>, so that the sound font is loaded
868 fox2mike 1.51 every time the system starts up.
869 erwin 1.26 </p>
870    
871 fox2mike 1.51 <note>
872 nightmorph 1.80 <path>/mnt</path> paths mentioned in the code listing(s) below will <e>not</e>
873     be the same in your machine. They are just an example. Please be careful to
874 fox2mike 1.51 change the path to suit your machine.
875     </note>
876 erwin 1.26
877 fox2mike 1.51 <pre caption="Loading Soundfonts">
878     <comment>(First, copy the Soundfont)</comment>
879 fox2mike 1.61 # <i>cp /mnt/win2k/Program\ Files/CreativeSBLive2k/SFBank/8MBGMSFX.SF2 /usr/share/sounds/sf2/</i>
880     <comment>(Or get it from your SoundBlaster CD)</comment>
881     # <i>cp /mnt/cdrom/AUDIO/ENGLISH/SFBANK/8MBGMSFX.SF2 /usr/share/sounds/sf2/</i>
882 fox2mike 1.51 <comment>(We load the specific Soundfont)</comment>
883     # <i>asfxload /usr/share/sounds/sf2/8MBGMSFX.SF2</i>
884 erwin 1.26 </pre>
885    
886 swift 1.35 <p>
887 nightmorph 1.80 You can now play midi files using a program like <c>aplaymidi</c>. Run
888     <c>aplaymidi -l</c> to get a list of available ports and then pick one
889 fox2mike 1.51 to play the file on.
890 swift 1.35 </p>
891 erwin 1.26
892 fox2mike 1.51 <pre caption="Playing MIDI">
893     <comment>(Check open ports)</comment>
894     # <i>aplaymidi -l</i>
895     Port Client name Port name
896     64:0 EMU10K1 MPU-401 (UART) EMU10K1 MPU-401 (UART)
897     65:0 Emu10k1 WaveTable Emu10k1 Port 0
898     65:1 Emu10k1 WaveTable Emu10k1 Port 1
899     65:2 Emu10k1 WaveTable Emu10k1 Port 2
900     65:3 Emu10k1 WaveTable Emu10k1 Port 3
901     <comment>(Pick a port, and play a mid file)</comment>
902     # <i> aplaymidi --port=65:0 /mnt/shyam/music/midi/mi2.mid</i>
903     </pre>
904 swift 1.32
905 erwin 1.26 </body>
906     </section>
907 fox2mike 1.51 <section id="vsynth">
908     <title>Virtual Synthesizers</title>
909 erwin 1.26 <body>
910    
911     <p>
912 fox2mike 1.51 If your sound card lacks a hardware synthesizer, you could use a virtual one
913     like <c>timidity++</c>. Installation is a breeze.
914 erwin 1.26 </p>
915    
916 fox2mike 1.51 <pre caption="Installing timidity++">
917 erwin 1.26 # <i>emerge timidity++</i>
918     </pre>
919    
920     <p>
921 nightmorph 1.71 For timidity to play sounds, it needs a sound font. Fortunately, the ebuild will
922     install some sound font packages for you. There are a few other font packages
923     available in Portage, such as <c>timidity-freepats</c> and
924     <c>timidity-eawpatches</c>. You can have multiple sound font configurations
925 nightmorph 1.80 installed, and you can place your own in <path>/usr/share/timidity/</path>. To
926 nightmorph 1.73 switch between different timidity configurations, you should use
927     <c>eselect</c>.
928 cam 1.33 </p>
929    
930 nightmorph 1.71 <pre caption="Changing configurations">
931     # <i>eselect timidity list</i>
932     # <i>eselect timidity set eawpatches</i>
933 cam 1.33 </pre>
934    
935     <p>
936 swift 1.35 Don't forget to add <c>timidity</c> to the default runlevel.
937 erwin 1.26 </p>
938    
939 swift 1.35 <pre caption="Adding timidity to the default runlevel">
940 erwin 1.26 # <i>rc-update add timidity default</i>
941     # <i>/etc/init.d/timidity start</i>
942     </pre>
943    
944 drobbins 1.1 <p>
945 fox2mike 1.51 You can now try out <uri link="#doc_chap4_pre3">Playing MIDI</uri> files.
946 erwin 1.26 </p>
947    
948 drobbins 1.1 </body>
949     </section>
950     <section>
951 swift 1.35 <title>Tools and Firmware</title>
952 drobbins 1.1 <body>
953 swift 1.20
954     <p>
955 swift 1.35 Some specific sound cards can benefit from certain tools provided by the
956 nightmorph 1.71 <c>alsa-tools</c> and <c>alsa-firmware</c> packages. You may install either with
957     a simple <c>emerge</c>.
958     </p>
959    
960     <pre caption="Installing ALSA Tools">
961     # <i>emerge alsa-tools</i>
962     </pre>
963    
964     </body>
965     </section>
966     <section>
967     <title>Multiple sound cards</title>
968     <body>
969    
970     <p>
971 nightmorph 1.74 You can have more than one sound card in your system simultaneously, provided
972     that you have built ALSA as modules in your kernel (or have installed
973 nightmorph 1.80 <c>alsa-driver</c> instead). You just need to specify which should be started
974 nightmorph 1.71 first in <path>/etc/modules.d/alsa</path>. Your cards are identified by their
975     driver names inside this file. 0 is the first card, 1 is the second, and so on.
976     Here's an example for a system with two sound cards.
977     </p>
978    
979     <pre caption="Two sound cards in /etc/modules.d/alsa">
980     options snd-emu10k1 index=0
981     options snd-via82xx index=1
982     </pre>
983    
984     <p>
985     Or, if you have two cards that use the same driver, you specify them on the same
986     line, using comma-separated numbers. Here's an example for a system with three
987     sound cards, two of which are the same Intel High Definition Audio card.
988 swift 1.20 </p>
989    
990 nightmorph 1.71 <pre caption="Multiple sound cards in /etc/modules.d/alsa">
991     options snd-ymfpci index=0
992     options snd-hda-intel index=1,2
993 drobbins 1.1 </pre>
994 swift 1.20
995 nightmorph 1.71 </body>
996     </section>
997     <section>
998     <title>Plugins</title>
999     <body>
1000    
1001 erwin 1.26 <p>
1002 nightmorph 1.71 You may want to install some plugins for extra functionality.
1003     <c>alsa-plugins</c> is a collection of useful plugins, which include: PulseAudio
1004     output, a sample rate converter, jack (a low-latency audio server), and an
1005     encoder that lets you output 6-channel audio through digital S/PDIF connections
1006     (both optical and coaxial). You can choose which of its plugins you want
1007     installed by adding their USE flags to <path>/etc/portage/package.use</path>.
1008 erwin 1.26 </p>
1009    
1010 nightmorph 1.71 <pre caption="Installing alsa-plugins">
1011     # <i>emerge -avt alsa-plugins</i>
1012 erwin 1.26 </pre>
1013    
1014     </body>
1015     </section>
1016     <section>
1017 nightmorph 1.71 <title>A big thank you to...</title>
1018 swift 1.21 <body>
1019    
1020     <p>
1021 fox2mike 1.51 Everyone who contributed to the earlier version of the Gentoo ALSA Guide:
1022 nightmorph 1.80 Vincent Verleye, Grant Goodyear, Arcady Genkin, Jeremy Huddleston,
1023 fox2mike 1.51 John P. Davis, Sven Vermeulen, Benny Chuang, Tiemo Kieft and Erwin.
1024 swift 1.21 </p>
1025    
1026 swift 1.17 </body>
1027     </section>
1028 drobbins 1.1 <section>
1029 fox2mike 1.51 <title>References</title>
1030 drobbins 1.1 <body>
1031 swift 1.20
1032 drobbins 1.1 <ul>
1033 fox2mike 1.51 <li><uri link="http://www.alsa-project.org/">The ALSA Project</uri></li>
1034 swift 1.35 <li><uri link="http://linux-sound.org">Linux Sound/MIDI Software</uri></li>
1035 drobbins 1.1 </ul>
1036 swift 1.20
1037 drobbins 1.1 </body>
1038     </section>
1039     </chapter>
1040     </guide>

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