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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 1.37 2004/06/15 07:21:07 bennyc Exp $ --> 2<!-- $Header: /var/cvsroot/gentoo/xml/htdocs/doc/en/alsa-guide.xml,v 1.60 2005/08/30 11:38:02 fox2mike 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">
11 <mail link="g2boojum@gentoo.org">Grant Goodyear</mail>
12</author>
13<author title="Author">
14 <mail link="agenkin@gentoo.org">Arcady Genkin</mail>
15</author>
16<author title="Author">
17 <mail link="eradicator@gentoo.org">Jeremy Huddleston</mail>
18</author>
19<author title="Editor"><!-- zhen@gentoo.org -->
20 John P. Davis
21</author>
22<author title="Editor">
23 <mail link="swift@gentoo.org">Sven Vermeulen</mail>
24</author>
25<author title="Editor">
26 <mail link="bennyc@gentoo.org">Benny Chuang</mail>
27</author>
28<author title="Editor">
29 <mail link="blubber@gentoo.org">Tiemo Kieft</mail>
30</author>
31<author title="Editor">
32 <mail link="erwin@gentoo.org">Erwin</mail>
33</author>
34 12
35<abstract> 13<abstract>
36This guide will show you how to set up the Advanced Linux Sound Architecture 14This document helps a user setup ALSA on Gentoo Linux.
37(ALSA) on Gentoo Linux. In addition to the Gentoo Linux Desktop Configuration
38Guide, this guide is supposed to give you more information on this subject.
39</abstract> 15</abstract>
40 16
17<!-- The content of this document is licensed under the CC-BY-SA license -->
18<!-- See http://creativecommons.org/licenses/by-sa/2.5 -->
41<license/> 19<license/>
42 20
43<version>1.5.0</version> 21<version>2.8</version>
44<date>May 18, 2004</date> 22<date>2005-08-30</date>
45 23
46<chapter> 24<chapter>
47<title>The Advanced Linux Sound Architecture</title> 25<title>Introduction</title>
48<section> 26<section>
49<title>What is ALSA?</title> 27<title>What is ALSA?</title>
50<body> 28<body>
51 29
52<p> 30<p>
53ALSA is the <e>Advanced Linux Sound Architecture</e>, a project dedicated to the 31ALSA, which stands for <e>Advanced Linux Sound Architecture</e>, provides
54development of a high-quality Linux sound subsystem. It has replaced OSS 32audio and MIDI (<e>Musical Instrument Digital Interface</e>) functionality to
55(<e>Open Sound System</e>) as default sound subsystem in the 2.6 kernel series. 33the Linux operating system. ALSA is the default sound subsystem in the 2.6
56</p> 34kernel thereby replacing OSS (<e>Open Sound System</e>), which was used in the
57 352.4 kernels.
58<p> 36</p>
59ALSA provides efficient support for all types of audio interfaces, is fully 37
60modularized, is SMP and thread-safe and provides a high-quality user space 38<p>
61library called <e>alsa-lib</e> to simplify application programming. It also 39ALSA's main features include efficient support for all types of audio
62provides a backwards compatibility layer with OSS. 40interfaces ranging from consumer sound cards to professional sound
41equipment, fully modularized drivers, SMP and thread safety, backward
42compatibility with OSS and a user-space library <c>alsa-lib</c> to make
43application development a breeze.
44</p>
45
46</body>
47</section>
48<section>
49<title>ALSA on Gentoo</title>
50<body>
51
52<p>
53One of Gentoo's main strengths lies in giving the user maximum control over
54how a system is installed/configured. ALSA on Gentoo follows the same
55principle. There are two ways you can get ALSA support up and running on your
56system. We shall look at them in detail in the next chapter.
63</p> 57</p>
64 58
65</body> 59</body>
66</section> 60</section>
67</chapter> 61</chapter>
62
68<chapter> 63<chapter>
69<title>Installing ALSA</title> 64<title>Installing ALSA</title>
70<section> 65<section>
71<title>USE Flags</title> 66<title>Options</title>
72<body>
73
74<p>
75Gentoo provides an <c>alsa</c> USE flag which you should set in
76<path>/etc/make.conf</path> to allow our available packages to compile with
77ALSA support. If you have <c>oss</c> in your USE variable as well, ALSA will
78compile with OSS backward compatibility.
79</p>
80
81</body> 67<body>
82</section> 68
69<warn>
70The methods shown below are mutually exclusive. You cannot have ALSA compiled
71in your kernel and use <c>media-sound/alsa-driver</c>. It <e>will</e> fail.
72</warn>
73
74<p>
75The two options are :
76</p>
77
78<ol>
79 <li>
80 Use ALSA provided by your kernel. This is the preferred/recommended
81 method.
82 </li>
83 <li>
84 Use Gentoo's <c>media-sound/alsa-driver</c> package.
85 </li>
86</ol>
87
88<p>
89We shall take a peek into both before finally deciding on one.
90</p>
91
92<p>
93If you were to use ALSA provided by the kernel, the following are the pros and
94cons :
95</p>
96
97<table>
98<tr>
99 <th>Kernel ALSA</th>
100 <th>Pros and Cons</th>
101</tr>
102<tr>
103 <th>+</th>
104 <ti>Pretty stable as drivers are integrated into kernel.</ti>
105</tr>
106<tr>
107 <th>+</th>
108 <ti>One shot solution, no repeating emerges.</ti>
109</tr>
110<tr>
111 <th>-</th>
112 <ti>Might be a slightly older version than <c>alsa-driver</c>.</ti>
113</tr>
114</table>
115
116<p>
117And, if you were to use alsa-driver,
118</p>
119
120<table>
121<tr>
122 <th>alsa-driver</th>
123 <th>Pros and Cons</th>
124</tr>
125<tr>
126 <th>+</th>
127 <ti>Latest drivers from the ALSA Project.</ti>
128</tr>
129<tr>
130 <th>-</th>
131 <ti>Every kernel recompile requires a re-emerge of <c>alsa-driver</c>.</ti>
132</tr>
133<tr>
134 <th>-</th>
135 <ti>Needs certain kernel config options disabled to work correctly.</ti>
136</tr>
137</table>
138
139</body>
83<section> 140</section>
84<title>Kernel Modules</title> 141<section>
142<title>So...</title>
143<body>
144
145<p>
146The main difference between using <c>alsa-driver</c> and ALSA that comes with
147the kernel is that <c>alsa-driver</c> is generally more up to date than the
148version in the kernel. Since this does not make any huge difference as
149such, you are encouraged to use the ALSA provided by the kernel for ease of use.
150Before reporting any sound related issues to <uri
151link="https://bugs.gentoo.org">Gentoo Bugzilla</uri>, please try to reproduce
152them using <c>alsa-driver</c> and file the bug report no matter what the
153result.
154</p>
155
85<body> 156</body>
157</section>
158<section id="lspci">
159<title>Before you proceed</title>
160<body>
86 161
87<p>
88First of all, before continuing, make sure your kernel has <e>Sound Card
89Support</e> enabled. If you used <c>genkernel</c> to build your kernel, then
90this is automatically true. Otherwise reconfigure your kernel.
91</p> 162<p>
92 163Whichever method of install you choose, you need to know what drivers your
164sound card uses. In most cases, sound cards (onboard and otherwise) are PCI
165based and <c>lspci</c> will help you in digging out the required information.
166Please <c>emerge sys-apps/pciutils</c> to get <c>lspci</c>, if you don't have it
167installed already. In case you have a USB sound card, <c>lsusb</c> from
168<c>sys-apps/usbutils</c> <e>might</e> be of help. For ISA cards, try using
169<c>sys-apps/isapnptools</c>. Also, the following pages <e>may</e> help users
170with ISA based sound cards.
93<p> 171</p>
94If you use a 2.6 kernel you can skip the rest of this section and continue with 172
95<uri link="#alsa-utils">Installing the ALSA Utils</uri> as 2.6 already has the 173<ul>
96necessary ALSA drivers in it. Of course, don't forget to enable support for the 174 <li>
97sound card you have when configuring your kernel. 175 <uri link="http://www.roestock.demon.co.uk/isapnptools/">The ISAPNPTOOLS
176 Page</uri>
177 </li>
178 <li>
179 <uri link="http://www2.linuxjournal.com/article/3269">LinuxJournal PnP
180 Article</uri>
181 </li>
182 <li>
183 <uri link="http://www.tldp.org/HOWTO/Sound-HOWTO/x320.html">TLDP Sound
184 HowTo</uri>
185 </li>
186</ul>
187
188<note>
189For ease of use/explanation, we assume the user has a PCI based sound card for
190the remainder of this guide.
191</note>
192
98</p> 193<p>
99 194We now proceed to find out details about the sound card.
100<p> 195</p>
101Users of 2.4 kernel sources will have to install the necessary ALSA drivers for 196
102their soundcard. First find out what soundcard you have. An easy trick is to 197<pre caption="Soundcard Details">
103search for "audio" in <path>/proc/pci</path>: 198# <i>lspci -v | grep -i audio</i>
1990000:00:0a.0 Multimedia audio controller: Creative Labs SB Live! EMU10k1 (rev 06)
200</pre>
201
104</p> 202<p>
105 203We now know that the sound card on the machine is a Sound Blaster Live! and
106<pre caption="Finding out the soundcard type"> 204the card manufacturer is Creative Labs. Head over to the
107# <i>grep -i audio /proc/pci</i> 205<uri link="http://www.alsa-project.org/alsa-doc/"> ALSA Soundcard Matrix</uri>
108Multimedia audio controller: VIA Technologies, Inc. VT82C686 AC97 Audio 206page and select Creative Labs from the drop down menu. You will be taken to
109Controller (rev 64). 207the Creative Labs matrix page where you can see that the SB Live! uses the
110</pre> 208<c>emu10k1</c> module. That is the information we need for now. If you are
111 209interested in detailed information, you can click on the link next to the
210"Details" and that will take you to the <c>emu10k1</c> specific page.
112<p> 211</p>
113Now go to the <uri link="http://www.alsa-project.org/alsa-doc">ALSA Soundcard 212
114Matrix</uri> and search for your soundcard. In the above example you should go 213</body>
115to the "VIA" manufacturer. You will receive a table with the known chipsets of 214</section>
116that vendor. The chipset in the above example is "via82c686"; the "Details" link 215<section id="kernel">
117then informs me that the driver is called <path>via82xx</path>. 216<title>Using ALSA provided by your Kernel</title>
217<body>
218
118</p> 219<p>
119 220If you're a person who likes to keep things simple like I do, then this is
221the way to go.
120<p> 222</p>
121Based on this information we can now install the <c>alsa-driver</c> for our 223
122soundcard. First edit <path>/etc/make.conf</path> and <e>add</e> a new option 224<note>
123called ALSA_CARDS to it. Inside this variable you declare the soundcard driver 225Since the 2005.0 release, Gentoo Linux uses 2.6 as the default kernel. Unless
124you want to use: 226you are specifically using the 2.4 profile, <c>gentoo-sources</c> will be a
2272.6 kernel on <e>most</e> architectures. Please check that your kernel is a
2282.6 series kernel. This method will <e>not</e> work on a 2.4 kernel.
229</note>
230
125</p> 231<p>
126 232Let us now configure the kernel to enable ALSA.
127<pre caption="Editing /etc/make.conf for ALSA_CARDS">
128ALSA_CARDS="via82xx"
129</pre>
130
131<p> 233</p>
132Now install <c>alsa-driver</c>: 234
235<impo>
236<c>genkernel</c> users should now run <c>genkernel --menuconfig all</c> and then follow
237the instructions in <uri link="#doc_chap2_pre3">Kernel Options for ALSA</uri>.
238</impo>
239
240<pre caption="Heading over to the source">
241# <i>cd /usr/src/linux</i>
242# <i>make menuconfig</i>
243</pre>
244
245<note>
246The above example assumes that <path>/usr/src/linux</path> symlink points to
247the kernel sources you want to use. Please ensure the same before proceeding.
248</note>
249
133</p> 250<p>
251Now we will look at some of the options we will have to enable in the 2.6
252kernel to ensure proper ALSA support for our sound card.
253</p>
134 254
255<p>
256Please note that for the sake of ease, all examples show ALSA built as modules.
257It is advisable to follow the same as it then allows the use of <c>alsaconf</c>
258which is a boon when you want to configure your card. Please do <e>not</e> skip the <uri
259link="#alsa-config">Configuration</uri> section of this document. If you still
260like to have options built-in, ensure that you make changes to your config
261accordingly.
262</p>
263
264<pre caption="Kernel Options for ALSA">
265Device Drivers ---&gt;
266 Sound ---&gt;
267
268<comment>(This needs to be enabled)</comment>
269&lt;M&gt; Sound card support
270
271<comment>(Make sure OSS is disabled)</comment>
272Open Sound System ---&gt;
273 &lt; &gt; Open Sound System (DEPRECATED)
274
275<comment>(Move one step back and enter ALSA)</comment>
276Advanced Linux Sound Architecture ---&gt;
277 &lt;M&gt; Advanced Linux Sound Architecture
278 <comment>(Select this if you want MIDI sequencing and routing)</comment>
279 &lt;M&gt; Sequencer support
280 <comment>(Old style /dev/mixer* and /dev/dsp* support. Recommended.)</comment>
281 &lt;M&gt; OSS Mixer API
282 &lt;M&gt; OSS PCM (digital audio) API
283
284<comment>(You now have a choice of devices to enable support for. Generally,
285you will have one type of device and not more. If you have more than one
286sound card, please enable them all here.)</comment>
287
288<comment>(Mostly for testing and development purposes, not needed for normal
289users unless you know what you are doing.)</comment>
290Generic devices ---&gt;
291
292<comment>(For ISA Sound cards)</comment>
293ISA devices ---&gt;
294<comment>(IF you had the Gravis, you would select this option)</comment>
295 &lt;M&gt; Gravis UltraSound Extreme
296
297<comment>(Move one level back and into PCI devices. Most sound cards today are
298PCI devices)</comment>
299PCI devices ---&gt;
300 <comment>(We now select the emu10k1 driver for our card)</comment>
301 &lt;M&gt; Emu10k1 (SB Live!, Audigy, E-mu APS)
302 <comment>(Or an Intel card would be)</comment>
303 &lt;M&gt; Intel/SiS/nVidia/AMD/ALi AC97 Controller
304 <comment>(Or if you have a VIA Card)</comment>
305 &lt;M&gt; VIA 82C686A/B, 8233/8235 AC97 Controller
306
307<comment>(Move one level back and select in case you have an USB sound card)</comment>
308USB Devices ---&gt;
309</pre>
310
311<p>
312Now that your options are set, you can (re)compile the kernel and ALSA support
313for your card should be functional once you reboot into the new kernel.
314You can now proceed to <uri link="#alsa-utilities">ALSA Utilities</uri> and
315see if everything is working as it should.
316</p>
317
318</body>
319</section>
320<section id="alsa-driver">
321<title>Using the ALSA Driver package</title>
322<body>
323
324<p>
325So you've decided to go the <c>alsa-driver</c> way. Let's get started then.
326There are a few minor things to be done to ensure only the drivers for your
327sound card are compiled. Although this is not really necessary, it cuts down
328on the unnecessary drivers that will be compiled otherwise.
329</p>
330
331<p>
332If you don't have an idea of what drivers your sound card might need, please
333take a look at the <uri link="#lspci">lspci</uri> section of this guide. Once
334you have your driver name (<c>emu10k1</c> in our example), edit
335<path>/etc/make.conf</path> and add a variable, <c>ALSA_CARDS</c>.
336</p>
337
338<pre caption="Adding ALSA_CARDS to make.conf">
339<comment>(For one sound card)</comment>
340ALSA_CARDS="emu10k1"
341<comment>(For more than one, separate names with spaces)</comment>
342ALSA_CARDS="emu10k1 via82xx"
343</pre>
344
345<p>
346If you have compiled your kernel and want to use <c>alsa-driver</c>, please
347ensure the following before proceeding, else <c>alsa-driver</c> is likely to
348fail. The next code listing gives you one way of performing the checks.
349</p>
350
351<note>
352<c>genkernel</c> users can proceed with <uri link="#doc_chap2_pre6">Installing
353alsa-driver</uri> as their configuration is in sync with the one shown below by
354default.
355</note>
356
357<ol>
358 <li>
359 <c>CONFIG_SOUND</c> is set. (Basic Sound support enabled)
360 </li>
361 <li>
362 <c>CONFIG_SOUND_PRIME</c> is not set. (In-built OSS support disabled)
363 </li>
364 <li>
365 <c>CONFIG_SND</c> is not set. (In-built ALSA support disabled)
366 </li>
367 <li>
368 <path>/usr/src/linux</path> points to the kernel you want ALSA working on.
369 </li>
370</ol>
371
372<pre caption=".config checks">
373<comment>(Assuming the linux symlink points to the correct kernel)</comment>
374# <i>cd /usr/src/linux</i>
375# <i>grep SOUND .config</i>
376<comment>(1. is true)</comment>
377CONFIG_SOUND=y
378<comment>(2. is true)</comment>
379CONFIG_SOUND_PRIME is not set
380# <i>grep SND .config</i>
381<comment>(and 3. is true)</comment>
382CONFIG_SND is not set
383</pre>
384
385<p>
386Now all you have to do is type the magic words... and no, it's not abracadabra.
387</p>
388
135<pre caption="Installing ALSA Drivers"> 389<pre caption="Installing alsa-driver">
136# <i>emerge alsa-driver</i> 390# <i>emerge alsa-driver</i>
137</pre> 391</pre>
138 392
139<impo> 393<impo>
140Whenever you (re)compile your kernel sources, chances are that the ALSA drivers 394Please note that you will have to run <c>emerge alsa-driver</c> after every
141will be overwritten. It is therefore adviseable to rerun <c>emerge 395kernel (re)compile, as the earlier drivers are deleted.
142alsa-driver</c> every time you (re)compile your kernel <e>after</e> having
143rebooted into the new kernel.
144</impo> 396</impo>
145 397
146</body> 398</body>
147</section> 399</section>
400</chapter>
401
402<chapter>
403<title>Configuring/Testing ALSA</title>
148<section id="alsa-utils"> 404<section id="alsa-utilities">
149<title>Installing the ALSA Utils</title> 405<title>ALSA Utilities</title>
150<body> 406<body>
151 407
152<p>
153If you want backwards compatibility with OSS, you need to install
154<c>alsa-oss</c>:
155</p> 408<p>
156 409<c>alsa-utils</c> forms an integral part of ALSA as it has a truckload of
157<pre caption="Installing the ALSA OSS compatibility layer"> 410programs that are highly useful, including the ALSA Initscripts. Hence we
158# <i>emerge alsa-oss</i> 411strongly recommend that you install <c>alsa-utils</c>
159</pre>
160
161<p> 412</p>
162Now install the ALSA Utils on your system (this is mandatory):
163</p>
164 413
165<pre caption="Installing ALSA Utils"> 414<pre caption="Install alsa-utils">
166# <i>emerge alsa-utils</i> 415# <i>emerge alsa-utils</i>
167</pre> 416</pre>
168 417
169<p> 418<note>
170Now that the utils are installed, it is time to configure ALSA... 419If you activated ALSA in your <uri link="#kernel">kernel</uri> <e>and</e> did
420not compile ALSA as modules, please proceed to the
421<uri link="#initscript">ALSA Initscript</uri> section. The rest of you need
422to configure ALSA. This is made very easy by the existence of the
423<c>alsaconf</c> tool provided by <c>alsa-utils</c>.
424</note>
425
426</body>
427</section>
428<section id="alsa-config">
429<title>Configuration</title>
430<body>
431
432<note>
433Please shut down any programs that <e>might</e> access the sound card while
434running <c>alsaconf</c>.
435</note>
436
171</p> 437<p>
438The easiest way to configure your sound card is to run <c>alsaconf</c>. Just
439type <c>alsaconf</c> in a shell as root.
440</p>
441
442<pre caption="Invoking alsaconf">
443# <i>alsaconf</i>
444</pre>
445
446<p>
447You will now see a neat menu guided interface that will automatically probe
448your devices and try to find out your sound card. You will be asked to pick
449your sound card from a list. Once that's done, it will ask you permission to
450automatically make required changes to <path>/etc/modules.d/alsa</path>.
451It will then adjust your volume settings to optimum levels, run
452<c>modules-update</c> and start the <path>/etc/init.d/alsasound</path> service.
453Once <c>alsaconf</c> exits, you can proceed with setting up the ALSA initscript.
454</p>
455
456</body>
457</section>
458<section id="initscript">
459<title>ALSA Initscript</title>
460<body>
461
462<p>
463We're now almost all setup. Whichever method you chose to install ALSA, you'll
464need to have something load your modules or initialize ALSA and restore your
465volume settings when your system comes up. The ALSA Initscript handles all of
466this for you and is called <c>alsasound</c>. Add it to the boot runlevel.
467</p>
468
469<pre caption="Adding ALSA to the boot runlevel">
470# <i>rc-update add alsasound boot</i>
471 * alsasound added to runlevel boot
472 * rc-update complete.
473</pre>
474
475<p>
476Next, just check the <path>/etc/conf.d/alsasound</path> file and ensure that
477SAVE_ON_STOP variable is set to yes. This saves your sound settings when you
478shutdown your system.
479</p>
480
481</body>
482</section>
483<section>
484<title>Audio Group</title>
485<body>
486
487<p>
488Before we move on to testing, there's one last <e>important</e> thing that needs
489to be setup. Rule of thumb in a *nix OS : Do not run as root unless needed.
490This applies here as well ;) How? Well, most of the times you should be logged
491in as a user and would like to listen to music or access your soundcard. For
492that to happen, you need to be in the "audio" group. At this point, we'll add
493users to the audio group, so that they won't have any issues when they want to
494access sound devices. We'll use <c>gpasswd</c> here and you need to be logged in
495as root for this to work.
496</p>
497
498<pre caption="Adding users to the audio group">
499<comment>(Substitute &lt;username&gt; with your user)</comment>
500# <i>gpasswd -a &lt;username&gt; audio </i>
501Adding user &lt;username&gt; to group audio
502</pre>
503
504</body>
505</section>
506<section>
507<title>Volume Check!</title>
508<body>
509
510<p>
511We've completed all the setups and pre-requisites, so let's fire up ALSA. If
512you ran <c>alsaconf</c>, you can skip this step, since <c>alsaconf</c> already
513does this for you.
514</p>
515
516<pre caption="Start the service">
517<comment>(ALSA as modules)</comment>
518# <i>/etc/init.d/alsasound start</i>
519 * Loading ALSA modules ...
520 * Loading: snd-card-0 ... [ ok ]
521 * Loading: snd-pcm-oss ... [ ok ]
522 * Loading: snd-seq ... [ ok ]
523 * Loading: snd-emu10k1-synth ... [ ok ]
524 * Loading: snd-seq-midi ... [ ok ]
525 * Restoring Mixer Levels ... [ ok ]
526<comment>(ALSA compiled in)</comment>
527# <i>/etc/init.d/alsasound start</i>
528 * Loading ALSA modules ...
529 * Restoring Mixer Levels ... [ ok ]
530</pre>
531
532<p>
533Now that the required things have been taken care of, we need to check up on
534the volume as in certain cases, it is muted. We use <c>alsamixer</c> for this
535purpose.
536</p>
537
538<pre caption="Starting alsamixer">
539<comment>(Opens up a console program. Only required settings are shown)</comment>
540# <i>alsamixer</i>
541</pre>
542
543<impo>
544If you have issues starting up <c>alsamixer</c> and get errors such as
545alsamixer: function snd_ctl_open failed for default: No such file or directory,
546this is usually an issue with udev setting up the devices. Run <c>killall
547udevd; udevstart</c> to reload <path>/dev</path> entries and fire up
548<c>alsamixer</c>. It should solve the issue.
549</impo>
550
551<p>
552This is how the ALSA Mixer <e>might</e> look the first time you open it. Pay
553attention to the Master and PCM channels which both have an MM below them.
554That means they are muted. If you try to play anything with <c>alsamixer</c>
555in this state, you will not hear anything on your speakers.
556</p>
557
558<figure link="/images/docs/alsa-mixermuted.png" short="AlsaMixer Muted" caption="The Alsa Mixer Main Window, Muted"/>
559
560<p>
561Now, we shall unmute the channels, and set volume levels as needed.
562</p>
563
564<warn>
565Both Master <e>and</e> PCM need to be unmuted and set to audible volume levels
566if you want to hear some output on your speakers.
567</warn>
568
569<ul>
570 <li>
571 To move between channels, use your left and right arrow keys. (&lt;-
572 &amp; -&gt;)
573 </li>
574 <li>
575 To toggle mute, move to the specific channel, for example Master and press
576 the <e>m</e> key on the keyboard.
577 </li>
578 <li>
579 To increase and decrease the volume levels, use the up and down arrow keys
580 respectively.
581 </li>
582</ul>
583
584<note>
585Be careful when setting your Bass and Treble values. 50 is usually a good
586number for both. Extremely high values of Bass may cause <e>jarring</e>
587on speakers that are not designed to handle them.
588</note>
589
590<p>
591After you're all done, your ALSA Mixer should look similar to the one below.
592Note the 00 instead of the MM and also the volume levels for some optimum
593settings.
594</p>
595
596<figure link="/images/docs/alsa-mixerunmuted.png" short="AlsaMixer Unmuted" caption="Alsa Mixer ready to roll"/>
597
598</body>
599</section>
600<section>
601<title>Sound Check!</title>
602<body>
603
604<p>
605The irritating way to check your soundcard is to see if you can hear static on
606the speakers. This isn't exactly fun, but hey, it tells you the card is
607configured and working.
608</p>
609
610<pre caption="Bring on the static">
611# <i>cat /dev/urandom > /dev/dsp</i>
612</pre>
613
614<note>
615<path>/dev/dsp</path> is a symlink to <path>/dev/sound/dsp</path> and should be
616automatically created. Try re-directing the output to
617<path>/dev/sound/dsp</path> in case you don't get a "No such file or directory"
618error.
619</note>
620
621<p>
622You should hear static. Press <c>Ctrl + C</c> to stop. If you don't hear
623anything, now is a good time to go back and check/trace out the issue and
624rectify it.
625</p>
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> or <c>xmms</c>. If you are an ogg fan, you could use
632<c>ogg123</c> provided by <c>media-sound/vorbis-tools</c>. Use any player you
633are comfortable with. As always, <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 xmms</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>
673</section>
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
684</body>
685</section>
686<section>
687<title>Issues?</title>
688<body>
689
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>
172 741
173</body> 742</body>
174</section> 743</section>
175</chapter> 744</chapter>
745
176<chapter> 746<chapter>
177<title>Configuring ALSA</title> 747<title>Other things ALSA</title>
178<section>
179<title>Automatically Loading the Kernel Modules</title>
180<body>
181
182<p>
183If you use a modular kernel (such as when using <c>genkernel</c>) you have to
184edit <path>/etc/modules.d/alsa</path> so that it activates the necesary modules
185at boot time. For the soundcard in our example:
186</p>
187
188<pre caption="/etc/modules.d/alsa">
189alias snd-card-0 snd-via82xx
190<comment># The following is only needed when you want OSS compatibility</comment>
191alias sound-slot-0 snd-card-0
192alias /dev/mixer snd-mixer-oss
193alias /dev/dsp snd-pcm-oss
194alias /dev/midi snd-seq-oss
195</pre>
196
197<p>
198Now run <c>modules-update</c> to save the changes you made to the
199<path>alsa</path> file into <path>/etc/modules.conf</path>:
200</p>
201
202<pre caption="Running modules-update">
203# <i>modules-update</i>
204</pre>
205
206</body>
207</section> 748<section>
208<section> 749<title>Setting up MIDI support</title>
209<title>Verifying the Device Files</title>
210<body>
211
212<p>
213If you use DevFS (which is the default for Gentoo installations) make sure that
214<path>/etc/devfsd.conf</path> has the ALSA devices and permissions correctly
215registered:
216</p>
217
218<pre caption="/etc/devfsd.conf">
219# ALSA/OSS stuff
220# Comment/change these if you want to change the permissions on
221# the audio devices
222LOOKUP snd MODLOAD ACTION snd
223LOOKUP dsp MODLOAD
224LOOKUP mixer MODLOAD
225LOOKUP midi MODLOAD
226REGISTER sound/.* PERMISSIONS root.audio 660
227REGISTER snd/.* PERMISSIONS root.audio 660
228</pre>
229
230</body> 750<body>
231</section>
232<section>
233<title>Having ALSA Activated at Boot</title>
234<body>
235 751
236<p>
237To activate ALSA support at boot, add the <c>alsasound</c> init script to the
238boot runlevel:
239</p> 752<p>
240 753If your sound card is one of those that come with on-board MIDI synthesizers
241<pre caption="Adding alsasound to the boot runlevel"> 754and you would like to listen to some .mid files, you have to install
242# <i>rc-update add alsasound boot</i> 755<c>awesfx</c> which is basically a set of utilities for controlling the AWE32
243# <i>/etc/init.d/alsasound start</i> 756driver. We need to install it first. If you don't have a hardware synthesizer,
244</pre> 757you can use a virtual one. Please see the section on
245 758<uri link="#vsynth">Virtual Synthesizers</uri> for more information.
246</body>
247</section>
248<section>
249<title>Unmute the Channels</title>
250<body>
251
252<p> 759</p>
253By default, all sound channels are muted. To fix this, run <c>amixer</c>:
254</p>
255 760
256<pre caption="Running amixer">
257# <i>amixer</i>
258</pre>
259
260<p>
261If <c>amixer</c> produces lots of output then you're ready to unmute the
262channels. If you receive an error, doublecheck that your soundcard module is
263started.
264</p>
265
266<p>
267Now unmute the <e>Master</e> and <e>PCM</e> channels. If this isn't sufficient,
268also unmute the <e>Center</e> and <e>Surround</e> channels.
269</p>
270
271<pre caption="Unmuting the sound channels">
272# <i>amixer set Master 100 unmute</i>
273# <i>amixer set PCM 100 unmute</i>
274<comment>(Only if the above isn't sufficient:)</comment>
275# <i>amixer set Center 100 unmute</i>
276# <i>amixer set Surround 100 unmute</i>
277</pre>
278
279<p>
280To check if your sound works, play a wave file (using <c>aplay</c>), mp3 (using
281<c>mpg123</c> or even <c>mplayer</c>) or any other sound file for that matter.
282</p>
283
284<p>
285To fine-tune the sound channel settings you can use the <c>alsamixer</c>
286application.
287</p>
288
289</body>
290</section>
291</chapter>
292<chapter>
293<title>Activating MIDI Support</title>
294<section>
295<title>Installing the Necessary Packages</title>
296<body>
297
298<p>
299Some soundcards come with onboard MIDI synthesizers. To use them, you must first
300install the <c>awesfx</c> package:
301</p>
302
303<pre caption="Installing the awesfx package"> 761<pre caption="Installing awesfx">
304# <i>emerge awesfx</i> 762# <i>emerge awesfx</i>
305</pre> 763</pre>
306 764
307<p> 765<note>
308If you have a collection of sound fonts somewhere, place them in 766You will need to copy over SoundFont (SF2) files from your sound card's driver
309<path>/usr/share/sfbank</path>. For instance, the SBLive has a sound font file 767CD or a Windows installation into <path>/usr/share/sounds/sf2/</path>. For
310called <path>8MBGMSFX.SF2</path> or <path>CT4GMSFX.SF2</path>. 768example a sound font file for the Creative SBLive! card would be 8MBGMSFX.SF2.
769</note>
770
311</p> 771<p>
312 772After copying over the Soundfont files, we can then play a midi file as shown.
773You can also add the <c>asfxload</c> command to
774<path>/etc/conf.d/local.start</path>, so that the sound font is loaded
775every time the system starts up.
313<p> 776</p>
314After copying over the sound font, select them using <c>sfxload</c>:
315</p>
316 777
778<note>
779<path>/mnt</path> paths mentioned in the code listing(s) below will <e>not</e>
780be the same in your machine. They are just an example. Please be careful to
781change the path to suit your machine.
782</note>
783
317<pre caption="Loading the sound font"> 784<pre caption="Loading Soundfonts">
785<comment>(First, copy the Soundfont)</comment>
786# <i>cp /mnt/win2k/Program\ Files/CreativeSBLive2k/SFBank/8MBGMSFX.SF2 /usr/share/sounds/sf2/</i>
787<comment>(We load the specific Soundfont)</comment>
318# <i>sfxload /usr/share/sfbank/8MBGMSFX.SF2</i> 788# <i>asfxload /usr/share/sounds/sf2/8MBGMSFX.SF2</i>
319</pre> 789</pre>
320 790
321<p>
322You must have this command run every time you boot, so it is adviseable to add
323it to <path>/etc/conf.d/local.start</path> as well.
324</p> 791<p>
325 792You can now play midi files using a program like <c>aplaymidi</c>. Run
793<c>aplaymidi -l</c> to get a list of available ports and then pick one
794to play the file on.
326<p> 795</p>
327If you can't find soundfonts on your driver CD you can download some online from 796
328<uri>http://www.parabola.demon.co.uk/alsa/awe64.html</uri>. 797<pre caption="Playing MIDI">
798<comment>(Check open ports)</comment>
799# <i>aplaymidi -l</i>
800 Port Client name Port name
801 64:0 EMU10K1 MPU-401 (UART) EMU10K1 MPU-401 (UART)
802 65:0 Emu10k1 WaveTable Emu10k1 Port 0
803 65:1 Emu10k1 WaveTable Emu10k1 Port 1
804 65:2 Emu10k1 WaveTable Emu10k1 Port 2
805 65:3 Emu10k1 WaveTable Emu10k1 Port 3
806<comment>(Pick a port, and play a mid file)</comment>
807# <i> aplaymidi --port=65:0 /mnt/shyam/music/midi/mi2.mid</i>
329</p> 808</pre>
330 809
331</body> 810</body>
332</section>
333<section> 811</section>
812<section id="vsynth">
334<title>Timidity++ Virtual Synthesizer</title> 813<title>Virtual Synthesizers</title>
335<body> 814<body>
336 815
337<p>
338If your sound card does not come with a hardware synthesizer (or you don't want
339to use it), you can use <c>timidity++</c> to provide you with a virtual
340synthesizer. Start by emerging this package:
341</p> 816<p>
817If your sound card lacks a hardware synthesizer, you could use a virtual one
818like <c>timidity++</c>. Installation is a breeze.
819</p>
342 820
343<pre caption="Installing Timidity++"> 821<pre caption="Installing timidity++">
344# <i>emerge timidity++</i> 822# <i>emerge timidity++</i>
345</pre> 823</pre>
346 824
347<p> 825<p>
348A sample configuration file will be installed for you in
349<path>/usr/share/timidity/config/timidity.cfg</path>. If you don't have a
350timidity++ configuration setup yet, you can just use this one.
351</p>
352
353<pre caption="Using the default Timidity++ configuration file">
354# <i>cp /usr/share/timidity/config/timidity.cfg /usr/share/timidity</i>
355</pre>
356
357<p>
358For timidity to play sounds, it needs a soundfont. If you do not have any, 826For timidity to play sounds, it needs a sound font. If you do not have any,
359install <c>timidity-eawpatches</c> which will give you some soundfonts. 827install <c>timidity-eawpatches</c> or <c>timidity-shompatches</c> which will
828give you some sound fonts. You can have multiple sound font configurations
829installed, and you can place your own in <path>/usr/share/timidity/</path>.
830To switch between different timidity configurations, you should use the
831<c>timidity-update</c> tool provided in the timidity++ package.
360</p> 832</p>
361 833
362<pre caption="Installing timidity-eawpatches"> 834<pre caption="Installing sound fonts">
363# <i>emerge timidity-eawpatches</i> 835# <i>emerge timidity-eawpatches</i>
836# <i>timidity-update -g -s eawpatches</i>
837
838<comment>(or)</comment>
839
840# <i>emerge timidity-shompatches</i>
841# <i>timidity-update -g -s shompatches</i>
364</pre> 842</pre>
365 843
366<p> 844<p>
367Don't forget to add <c>timidity</c> to the default runlevel. 845Don't forget to add <c>timidity</c> to the default runlevel.
368</p> 846</p>
370<pre caption="Adding timidity to the default runlevel"> 848<pre caption="Adding timidity to the default runlevel">
371# <i>rc-update add timidity default</i> 849# <i>rc-update add timidity default</i>
372# <i>/etc/init.d/timidity start</i> 850# <i>/etc/init.d/timidity start</i>
373</pre> 851</pre>
374 852
853<p>
854You can now try out <uri link="#doc_chap4_pre3">Playing MIDI</uri> files.
855</p>
856
375</body> 857</body>
376</section>
377<section> 858</section>
378<title>Testing MIDI Support</title>
379<body>
380
381<p>
382You can use <c>pmidi</c> to test your MIDI configuration:
383</p>
384
385<pre caption="Installing pmidi">
386# <i>emerge pmidi</i>
387</pre>
388
389<p>
390To see what MIDI output ports are available on your system, use the <c>-l</c>
391option:
392</p>
393
394<pre caption="Viewing the MIDI output ports">
395# <i>pmidi -l</i>
396</pre>
397
398<p>
399If all looks fine, try playing a MIDI file to make sure everything works. With
400the <c>-p</c> option you define what MIDI port you want to use.
401</p>
402
403<pre caption="Playing a MIDI file">
404# <i>pmidi -p 65:0 "Final Fantasy 7 - Aerith' Theme.mid"</i>
405</pre>
406
407</body>
408</section>
409</chapter>
410<chapter>
411<title>Final Remarks</title>
412<section> 859<section>
413<title>Tools and Firmware</title> 860<title>Tools and Firmware</title>
414<body> 861<body>
415 862
416<p> 863<p>
423<pre caption="Selecting ALSA Tools in /etc/make.conf"> 870<pre caption="Selecting ALSA Tools in /etc/make.conf">
424ALSA_TOOLS="as10k1 ac3dec" 871ALSA_TOOLS="as10k1 ac3dec"
425</pre> 872</pre>
426 873
427<p> 874<p>
875If the ALSA_TOOLS variable is not set, all available tools will be built.
428Then install the <c>alsa-tools</c> (and/or <c>alsa-firmware</c>) package(s): 876Now, install the <c>alsa-tools</c> (and/or <c>alsa-firmware</c>) package(s):
429</p> 877</p>
430 878
431<pre caption="Installing ALSA Tools"> 879<pre caption="Installing ALSA Tools">
432# <i>emerge alsa-tools</i> 880# <i>emerge alsa-tools</i>
433</pre> 881</pre>
434 882
435</body> 883</body>
436</section> 884</section>
437<section> 885<section>
438<title>Activating Joystick Support</title> 886<title>A Big thank you to...</title>
439<body>
440
441<p>
442If your soundcard has a joystick plug, you might be interested in activating
443joystick support for your soundcard. If so, start by verifying if your soundcard
444driver has a joystick parameter. You can verify this by running <c>modinfo</c>
445against your kernel module. For instance, for the <c>snd-via82xx</c>:
446</p>
447
448<pre caption="Running modinfo">
449# <i>modinfo snd-via82xx</i>
450filename: /lib/modules/2.4.22-ck2/snd-via82xx.o
451description: "VIA VT82xx audio"
452author: "Jaroslav Kysela &lt;perex@suse.cz&gt;"
453license: "GPL"
454parm: index int array (min = 1, max = 8), description "Index value for
455 VIA 82xx bridge."
456parm: id string array (min = 1, max = 8), description "ID string for VIA
457 82xx bridge."
458parm: enable int array (min = 1, max = 8), description "Enable audio part
459 of VIA 82xx bridge."
460parm: mpu_port long array (min = 1, max = 8), description "MPU-401 port.
461 (VT82C686x only)"
462<i>parm: joystick int array (min = 1, max = 8), description "Enable
463 joystick. (VT82C686x only)"</i>
464parm: ac97_clock int array (min = 1, max = 8), description "AC'97 codec
465 clock (default 48000Hz)."
466parm: dxs_support int array (min = 1, max = 8), description "Support for
467 DXS channels (0 = auto, 1 = enable, 2 = disable, 3 = 48k only, 4 =
468 no VRA)
469</pre>
470
471<p>
472If it has the <c>joystick</c> parameter, append <c>joystick=1</c> to your
473<c>options</c> line in <path>/etc/modules.d/alsa</path>. For instance:
474</p>
475
476<pre caption="Adding the joystick parameter">
477alias snd-card-0 snd-via82xx
478options snd-via82xx joystick=1
479</pre>
480
481</body> 887<body>
482</section> 888
889<p>
890Everyone who contributed to the earlier version of the Gentoo ALSA Guide:
891Vincent Verleye, Grant Goodyear, Arcady Genkin, Jeremy Huddleston,
892John P. Davis, Sven Vermeulen, Benny Chuang, Tiemo Kieft and Erwin.
893</p>
894
895</body>
483<section> 896</section>
897<section>
484<title>Resources</title> 898<title>References</title>
485<body> 899<body>
486 900
487<ul> 901<ul>
488 <li><uri link="http://www.alsa-project.org">The ALSA Project</uri></li> 902 <li><uri link="http://www.alsa-project.org/">The ALSA Project</uri></li>
489 <li><uri link="http://www.djcj.org">ALSA Howto's and FAQs</uri></li>
490 <li><uri link="http://linux-sound.org">Linux Sound/MIDI Software</uri></li> 903 <li><uri link="http://linux-sound.org">Linux Sound/MIDI Software</uri></li>
491</ul> 904</ul>
492 905
493</body> 906</body>
494</section> 907</section>

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