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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 1.56 2005/07/14 09:11:02 neysx 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>2.5</version>
44<date>May 18, 2004</date> 22<date>2005-07-14</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.
150</p>
151
85<body> 152</body>
153</section>
154<section id="lspci">
155<title>Before you proceed</title>
156<body>
86 157
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> 158<p>
92 159Whichever method of install you choose, you need to know what drivers your
160sound card uses. In most cases, sound cards (onboard and otherwise) are PCI
161based and <c>lspci</c> will help you in digging out the required information.
162Please <c>emerge sys-apps/pciutils</c> to get <c>lspci</c>, if you don't have it
163installed already. In case you have a USB sound card, <c>lsusb</c> from
164<c>sys-apps/usbutils</c> <e>might</e> be of help. For ISA cards, try using
165<c>sys-apps/isapnptools</c>. Also, the following pages <e>may</e> help users
166with ISA based sound cards.
93<p> 167</p>
94If you use a 2.6 kernel you can skip the rest of this section and continue with 168
95<uri link="#alsa-utils">Installing the ALSA Utils</uri> as 2.6 already has the 169<ul>
96necessary ALSA drivers in it. Of course, don't forget to enable support for the 170 <li>
97sound card you have when configuring your kernel. 171 <uri link="http://www.roestock.demon.co.uk/isapnptools/">The ISAPNPTOOLS
172 Page</uri>
173 </li>
174 <li>
175 <uri link="http://www2.linuxjournal.com/article/3269">LinuxJournal PnP
176 Article</uri>
177 </li>
178 <li>
179 <uri link="http://www.tldp.org/HOWTO/Sound-HOWTO/x320.html">TLDP Sound
180 HowTo</uri>
181 </li>
182</ul>
183
184<note>
185For ease of use/explanation, we assume the user has a PCI based sound card for
186the remainder of this guide.
187</note>
188
98</p> 189<p>
99 190We now proceed to find out details about the sound card.
100<p> 191</p>
101Users of 2.4 kernel sources will have to install the necessary ALSA drivers for 192
102their soundcard. First find out what soundcard you have. An easy trick is to 193<pre caption="Soundcard Details">
103search for "audio" in <path>/proc/pci</path>: 194# <i>lspci -v | grep -i audio</i>
1950000:00:0a.0 Multimedia audio controller: Creative Labs SB Live! EMU10k1 (rev 06)
196</pre>
197
104</p> 198<p>
105 199We now know that the sound card on the machine is a Sound Blaster Live! and
106<pre caption="Finding out the soundcard type"> 200the card manufacturer is Creative Labs. Head over to the
107# <i>grep -i audio /proc/pci</i> 201<uri link="http://www.alsa-project.org/alsa-doc/"> ALSA Soundcard Matrix</uri>
108Multimedia audio controller: VIA Technologies, Inc. VT82C686 AC97 Audio 202page and select Creative Labs from the drop down menu. You will be taken to
109Controller (rev 64). 203the Creative Labs matrix page where you can see that the SB Live! uses the
110</pre> 204<c>emu10k1</c> module. That is the information we need for now. If you are
111 205interested in detailed information, you can click on the link next to the
206"Details" and that will take you to the <c>emu10k1</c> specific page.
112<p> 207</p>
113Now go to the <uri link="http://www.alsa-project.org/alsa-doc">ALSA Soundcard 208
114Matrix</uri> and search for your soundcard. In the above example you should go 209</body>
115to the "VIA" manufacturer. You will receive a table with the known chipsets of 210</section>
116that vendor. The chipset in the above example is "via82c686"; the "Details" link 211<section id="kernel">
117then informs me that the driver is called <path>via82xx</path>. 212<title>Using ALSA provided by your Kernel</title>
213<body>
214
118</p> 215<p>
119 216If you're a person who likes to keep things simple like I do, then this is
217the way to go.
120<p> 218</p>
121Based on this information we can now install the <c>alsa-driver</c> for our 219
122soundcard. First edit <path>/etc/make.conf</path> and <e>add</e> a new option 220<note>
123called ALSA_CARDS to it. Inside this variable you declare the soundcard driver 221Since the 2005.0 release, Gentoo Linux uses 2.6 as the default kernel. Unless
124you want to use: 222you are specifically using the 2.4 profile, <c>gentoo-sources</c> will be a
2232.6 kernel on <e>most</e> architectures. Please check that your kernel is a
2242.6 series kernel. This method will <e>not</e> work on a 2.4 kernel.
225</note>
226
125</p> 227<p>
126 228Let 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> 229</p>
132Now install <c>alsa-driver</c>: 230
231<impo>
232<c>genkernel</c> users should now run <c>genkernel --menuconfig</c> and then follow
233the instructions in <uri link="#doc_chap2_pre3">Kernel Options for ALSA</uri>.
234</impo>
235
236<pre caption="Heading over to the source">
237# <i>cd /usr/src/linux</i>
238# <i>make menuconfig</i>
239</pre>
240
241<note>
242The above example assumes that <path>/usr/src/linux</path> symlink points to
243the kernel sources you want to use. Please ensure the same before proceeding.
244</note>
245
133</p> 246<p>
247Now we will look at some of the options we will have to enable in the 2.6
248kernel to ensure proper ALSA support for our sound card.
249</p>
134 250
251<p>
252Please note that for the sake of ease, all examples show ALSA built as modules.
253It is advisable to follow the same as it then allows the use of <c>alsaconf</c>
254which is a boon when you want to configure your card. Please do <e>not</e> skip the <uri
255link="#alsa-config">Configuration</uri> section of this document. If you still
256like to have options built-in, ensure that you make changes to your config
257accordingly.
258</p>
259
260<pre caption="Kernel Options for ALSA">
261Device Drivers ---&gt;
262 Sound ---&gt;
263
264<comment>(This needs to be enabled)</comment>
265&lt;M&gt; Sound card support
266
267<comment>(Make sure OSS is disabled)</comment>
268Open Sound System ---&gt;
269 &lt; &gt; Open Sound System (DEPRECATED)
270
271<comment>(Move one step back and enter ALSA)</comment>
272Advanced Linux Sound Architecture ---&gt;
273 &lt;M&gt; Advanced Linux Sound Architecture
274 <comment>(Select this if you want MIDI sequencing and routing)</comment>
275 &lt;M&gt; Sequencer support
276 <comment>(Old style /dev/mixer* and /dev/dsp* support. Recommended.)</comment>
277 &lt;M&gt; OSS Mixer API
278 &lt;M&gt; OSS PCM (digital audio) API
279
280<comment>(You now have a choice of devices to enable support for. Generally,
281you will have one type of device and not more. If you have more than one
282sound card, please enable them all here.)</comment>
283
284<comment>(Mostly for testing and development purposes, not needed for normal
285users unless you know what you are doing.)</comment>
286Generic devices ---&gt;
287
288<comment>(For ISA Sound cards)</comment>
289ISA devices ---&gt;
290<comment>(IF you had the Gravis, you would select this option)</comment>
291 &lt;M&gt; Gravis UltraSound Extreme
292
293<comment>(Move one level back and into PCI devices. Most sound cards today are
294PCI devices)</comment>
295PCI devices ---&gt;
296 <comment>(We now select the emu10k1 driver for our card)</comment>
297 &lt;M&gt; Emu10k1 (SB Live!, Audigy, E-mu APS)
298 <comment>(Or an Intel card would be)</comment>
299 &lt;M&gt; Intel/SiS/nVidia/AMD/ALi AC97 Controller
300 <comment>(Or if you have a VIA Card)</comment>
301 &lt;M&gt; VIA 82C686A/B, 8233/8235 AC97 Controller
302
303<comment>(Move one level back and select in case you have an USB sound card)</comment>
304USB Devices ---&gt;
305</pre>
306
307<p>
308Now that your options are set, you can (re)compile the kernel and ALSA support
309for your card should be functional once you reboot into the new kernel.
310You can now proceed to <uri link="#alsa-utilities">ALSA Utilities</uri> and
311see if everything is working as it should.
312</p>
313
314</body>
315</section>
316<section id="alsa-driver">
317<title>Using the ALSA Driver package</title>
318<body>
319
320<p>
321So you've decided to go the <c>alsa-driver</c> way. Let's get started then.
322There are a few minor things to be done to ensure only the drivers for your
323sound card are compiled. Although this is not really necessary, it cuts down
324on the unnecessary drivers that will be compiled otherwise.
325</p>
326
327<p>
328If you don't have an idea of what drivers your sound card might need, please
329take a look at the <uri link="#lspci">lspci</uri> section of this guide. Once
330you have your driver name (<c>emu10k1</c> in our example), edit
331<path>/etc/make.conf</path> and add a variable, <c>ALSA_CARDS</c>.
332</p>
333
334<pre caption="Adding ALSA_CARDS to make.conf">
335<comment>(For one sound card)</comment>
336ALSA_CARDS="emu10k1"
337<comment>(For more than one, seperate names with spaces)</comment>
338ALSA_CARDS="emu10k1 via82xx"
339</pre>
340
341<p>
342If you have compiled your kernel and want to use <c>alsa-driver</c>, please
343ensure the following before proceeding, else <c>alsa-driver</c> is likely to
344fail. The next code listing gives you one way of performing the checks.
345</p>
346
347<note>
348<c>genkernel</c> users can proceed with <uri link="#doc_chap2_pre6">Installing
349alsa-driver</uri> as their configuration is in sync with the one shown below by
350default.
351</note>
352
353<ol>
354 <li>
355 <c>CONFIG_SOUND</c> is set. (Basic Sound support enabled)
356 </li>
357 <li>
358 <c>CONFIG_SOUND_PRIME</c> is not set. (In-built OSS support disabled)
359 </li>
360 <li>
361 <c>CONFIG_SND</c> is not set. (In-built ALSA support disabled)
362 </li>
363 <li>
364 <path>/usr/src/linux</path> points to the kernel you want ALSA working on.
365 </li>
366</ol>
367
368<pre caption=".config checks">
369<comment>(Assuming the linux symlink points to the correct kernel)</comment>
370# <i>cd /usr/src/linux</i>
371# <i>grep SOUND .config</i>
372<comment>(1. is true)</comment>
373CONFIG_SOUND=y
374<comment>(2. is true)</comment>
375CONFIG_SOUND_PRIME is not set
376# <i>grep SND .config</i>
377<comment>(and 3. is true)</comment>
378CONFIG_SND is not set
379</pre>
380
381<p>
382Now all you have to do is type the magic words... and no, it's not abracadabra.
383</p>
384
135<pre caption="Installing ALSA Drivers"> 385<pre caption="Installing alsa-driver">
136# <i>emerge alsa-driver</i> 386# <i>emerge alsa-driver</i>
137</pre> 387</pre>
138 388
139<impo> 389<impo>
140Whenever you (re)compile your kernel sources, chances are that the ALSA drivers 390Please 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 391kernel (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> 392</impo>
145 393
146</body> 394</body>
147</section> 395</section>
396</chapter>
397
398<chapter>
399<title>Configuring/Testing ALSA</title>
148<section id="alsa-utils"> 400<section id="alsa-utilities">
149<title>Installing the ALSA Utils</title> 401<title>ALSA Utilities</title>
150<body> 402<body>
151 403
152<p>
153If you want backwards compatibility with OSS, you need to install
154<c>alsa-oss</c>:
155</p> 404<p>
156 405<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"> 406programs that are highly useful, including the ALSA Initscripts. Hence we
158# <i>emerge alsa-oss</i> 407strongly recommend that you install <c>alsa-utils</c>
159</pre>
160
161<p> 408</p>
162Now install the ALSA Utils on your system (this is mandatory):
163</p>
164 409
165<pre caption="Installing ALSA Utils"> 410<pre caption="Install alsa-utils">
166# <i>emerge alsa-utils</i> 411# <i>emerge alsa-utils</i>
167</pre> 412</pre>
168 413
169<p> 414<note>
170Now that the utils are installed, it is time to configure ALSA... 415If you activated ALSA in your <uri link="#kernel">kernel</uri> <e>and</e> did
416not compile ALSA as modules, please proceed to the
417<uri link="#initscript">ALSA Initscript</uri> section. The rest of you need
418to configure ALSA. This is made very easy by the existence of the
419<c>alsaconf</c> tool provided by <c>alsa-utils</c>.
420</note>
421
422</body>
423</section>
424<section id="alsa-config">
425<title>Configuration</title>
426<body>
427
428<note>
429Please shut down any programs that <e>might</e> access the sound card while
430running <c>alsaconf</c>.
431</note>
432
171</p> 433<p>
434The easiest way to configure your sound card is to run <c>alsaconf</c>. Just
435type <c>alsaconf</c> in a shell as root.
436</p>
437
438<pre caption="Invoking alsaconf">
439# <i>alsaconf</i>
440</pre>
441
442<p>
443You will now see a neat menu guided interface that will automatically probe
444your devices and try to find out your sound card. You will be asked to pick
445your sound card from a list. Once that's done, it will ask you permission to
446automatically make required changes to <path>/etc/modules.d/alsa</path>.
447It will then adjust your volume settings to optimum levels, run
448<c>modules-update</c> and start the <path>/etc/init.d/alsasound</path> service.
449Once <c>alsaconf</c> exits, you can proceed with setting up the ALSA initscript.
450</p>
451
452</body>
453</section>
454<section id="initscript">
455<title>ALSA Initscript</title>
456<body>
457
458<p>
459We're now almost all setup. Whichever method you chose to install ALSA, you'll
460need to have something load your modules or initialize ALSA and restore your
461volume settings when your system comes up. The ALSA Initscript handles all of
462this for you and is called <c>alsasound</c>. Add it to the boot runlevel.
463</p>
464
465<pre caption="Adding ALSA to the boot runlevel">
466# <i>rc-update add alsasound boot</i>
467 * alsasound added to runlevel boot
468 * rc-update complete.
469</pre>
470
471<p>
472Next, just check the <path>/etc/conf.d/alsasound</path> file and ensure that
473SAVE_ON_STOP variable is set to yes. This saves your sound settings when you
474shutdown your system.
475</p>
476
477</body>
478</section>
479<section>
480<title>Audio Group</title>
481<body>
482
483<p>
484Before we move on to testing, there's one last <e>important</e> thing that needs
485to be setup. Rule of thumb in a *nix OS : Do not run as root unless needed.
486This applies here as well ;) How? Well, most of the times you should be logged
487in as a user and would like to listen to music or access your soundcard. For
488that to happen, you need to be in the "audio" group. At this point, we'll add
489users to the audio group, so that they won't have any issues when they want to
490access sound devices. We'll use <c>gpasswd</c> here and you need to be logged in
491as root for this to work.
492</p>
493
494<pre caption="Adding users to the audio group">
495<comment>(Substitute &lt;username&gt; with your user)</comment>
496# <i>gpasswd -a &lt;username&gt; audio </i>
497Adding user &lt;username&gt; to group audio
498</pre>
499
500</body>
501</section>
502<section>
503<title>Volume Check!</title>
504<body>
505
506<p>
507We've completed all the setups and pre-requisites, so let's fire up ALSA. If
508you ran <c>alsaconf</c>, you can skip this step, since <c>alsaconf</c> already
509does this for you.
510</p>
511
512<pre caption="Start the service">
513<comment>(ALSA as modules)</comment>
514# <i>/etc/init.d/alsasound start</i>
515 * Loading ALSA modules ...
516 * Loading: snd-card-0 ... [ ok ]
517 * Loading: snd-pcm-oss ... [ ok ]
518 * Loading: snd-seq ... [ ok ]
519 * Loading: snd-emu10k1-synth ... [ ok ]
520 * Loading: snd-seq-midi ... [ ok ]
521 * Restoring Mixer Levels ... [ ok ]
522<comment>(ALSA compiled in)</comment>
523# <i>/etc/init.d/alsasound start</i>
524 * Loading ALSA modules ...
525 * Restoring Mixer Levels ... [ ok ]
526</pre>
527
528<p>
529Now that the required things have been taken care of, we need to check up on
530the volume as in certain cases, it is muted. We use <c>alsamixer</c> for this
531purpose.
532</p>
533
534<pre caption="Starting alsamixer">
535<comment>(Opens up a console program. Only required settings are shown)</comment>
536# <i>alsamixer</i>
537</pre>
538
539<impo>
540If you have issues starting up <c>alsamixer</c> and get errors such as
541alsamixer: function snd_ctl_open failed for default: No such file or directory,
542this is usually an issue with udev setting up the devices. Run <c>killall -9
543udevd; udevstart</c> to reload /dev entries and fire up <c>alsamixer</c>. It
544should solve the issue.
545</impo>
546
547<p>
548This is how the ALSA Mixer <e>might</e> look the first time you open it. Pay
549attention to the Master and PCM channels which both have an MM below them.
550That means they are muted. If you try to play anything with <c>alsamixer</c>
551in this state, you will not hear anything on your speakers.
552</p>
553
554<figure link="/images/docs/alsa-mixermuted.png" short="AlsaMixer Muted" caption="The Alsa Mixer Main Window, Muted"/>
555
556<p>
557Now, we shall unmute the channels, and set volume levels as needed.
558</p>
559
560<warn>
561Both Master <e>and</e> PCM need to be unmuted and set to audible volume levels
562if you want to hear some output on your speakers.
563</warn>
564
565<ul>
566 <li>
567 To move between channels, use your left and right arrow keys. (&lt;-
568 &amp; -&gt;)
569 </li>
570 <li>
571 To toggle mute, move to the specific channel, for example Master and press
572 the <e>m</e> key on the keyboard.
573 </li>
574 <li>
575 To increase and decrease the volume levels, use the up and down arrow keys
576 respectively.
577 </li>
578</ul>
579
580<note>
581Be careful when setting your Bass and Treble values. 50 is usually a good
582number for both. Extremely high values of Bass may cause <e>jarring</e>
583on speakers that are not designed to handle them.
584</note>
585
586<p>
587After you're all done, your ALSA Mixer should look similar to the one below.
588Note the 00 instead of the MM and also the volume levels for some optimum
589settings.
590</p>
591
592<figure link="/images/docs/alsa-mixerunmuted.png" short="AlsaMixer Unmuted" caption="Alsa Mixer ready to roll"/>
593
594</body>
595</section>
596<section>
597<title>Sound Check!</title>
598<body>
599
600<p>
601The irritating way to check your soundcard is to see if you can hear static on
602the speakers. This isn't exactly fun, but hey, it tells you the card is
603configured and working.
604</p>
605
606<pre caption="Bring on th static">
607# <i>cat /dev/urandom > /dev/dsp</i>
608</pre>
609
610<note>
611<path>/dev/dsp</path> is a symlink to <path>/dev/sound/dsp</path> and should be
612automatically created. Try re-directing the output to
613<path>/dev/sound/dsp</path> in case you don't get a "No such file or directory"
614error.
615</note>
616
617<p>
618You should hear static. Press <c>Ctrl + C</c> to stop. If you don't hear
619anything, now is a good time to go back and check/trace out the issue and
620rectify it.
621</p>
622
623<p>
624Finally. Some music. If everything above is perfect, you should now be able to
625listen to some good music. A quick way to test is to use a command line tool
626like <c>media-sound/madplay</c>. You could also use something more well known
627like <c>mpg123</c> or <c>xmms</c>. If you are an ogg fan, you could use
628<c>ogg123</c> provided by <c>media-sound/vorbis-tools</c>. Use any player you
629are comfortable with. As always, <c>emerge</c> what you need.
630</p>
631
632<pre caption="Getting the software">
633<comment>(Install the applications you want)</comment>
634# <i>emerge madplay mpg123 xmms</i>
635<comment>(To play .ogg files)</comment>
636# <i>emerge vorbis-tools</i>
637</pre>
638
639<p>
640And then play your favorite sound track...
641</p>
642
643<pre caption="Playing Music">
644# <i>madplay -v /mnt/shyam/Music/Paul\ Oakenfold\ -\ Dread\ Rock.mp3</i>
645MPEG Audio Decoder 0.15.2 (beta) - Copyright (C) 2000-2004 Robert Leslie et al.
646 Title: Dread Rock
647 Artist: Paul Oakenfold
648 Album: Matrix Reloaded
649 Year: 2003
650 Genre: Soundtrack
651 Soundtrack
652 00:04:19 Layer III, 160 kbps, 44100 Hz, joint stereo (MS), no CRC
653
654# <i>ogg123 Paul\ Oakenfold\ -\ Dread\ Rock.ogg</i>
655Audio Device: Advanced Linux Sound Architecture (ALSA) output
656
657Playing: Paul Oakenfold - Dread Rock.ogg
658Ogg Vorbis stream: 2 channel, 44100 Hz
659Genre: Soundtrack
660Transcoded: mp3;160
661Title: Dread Rock
662Artist: Paul Oakenfold
663Date: 2003
664Album: Matrix Reloaded
665Time: 00:11.31 [04:28.75] of 04:40.06 (200.6 kbps) Output Buffer 96.9%
666</pre>
667
668</body>
669</section>
670<section>
671<title> ALSA and USE</title>
672<body>
673
674<p>
675You can now add the <c>alsa</c> use flag to <path>/etc/make.conf</path> to
676ensure that your applications that support ALSA get built with it. Some
677architectures like x86 and amd64 have the flag enabled by default.
678</p>
679
680</body>
681</section>
682<section>
683<title>Issues?</title>
684<body>
685
686<p>
687If for some reason you're unable to hear sound, the first thing to do would
688be to check your <uri link="#doc_chap3_pre6">alsamixer</uri> settings. 80% of
689the issues lie with muted channels or low volume. Also check your Window
690Manager's sound applet and verify that volumes are set to audible levels.
691</p>
692
693<p>
694<path>/proc</path> is your friend. And in this case, <path>/proc/asound</path>
695is your best friend. We shall just take a short look at how much info is made
696available to us there.
697</p>
698
699<pre caption="Fun with /proc/asound">
700<comment>(First and foremost, if /proc/asound/cards shows your card, ALSA has
701picked up your sound card fine.)</comment>
702# <i>cat /proc/asound/cards</i>
7030 [Live ]: EMU10K1 - Sound Blaster Live!
704 Sound Blaster Live! (rev.6, serial:0x80271102) at 0xb800, irq 11
705
706<comment>(If you run ALSA off the kernel like I do and wonder how far behind
707you are from alsa-driver, this displays current running ALSA version)</comment>
708# <i>cat /proc/asound/version</i>
709Advanced Linux Sound Architecture Driver Version 1.0.8 (Thu Jan 13 09:39:32 2005 UTC).
710
711<comment>(ALSA OSS emulation details)</comment>
712# <i>cat /proc/asound/oss/sndstat</i>
713Sound Driver:3.8.1a-980706 (ALSA v1.0.8 emulation code)
714Kernel: Linux airwolf.zion 2.6.11ac1 #2 Wed May 4 00:35:08 IST 2005 i686
715Config options: 0
716
717Installed drivers:
718Type 10: ALSA emulation
719
720Card config:
721Sound Blaster Live! (rev.6, serial:0x80271102) at 0xb800, irq 11
722
723Audio devices:
7240: EMU10K1 (DUPLEX)
725
726Synth devices: NOT ENABLED IN CONFIG
727
728Midi devices:
7290: EMU10K1 MPU-401 (UART)
730
731Timers:
7327: system timer
733
734Mixers:
7350: SigmaTel STAC9721/23
736</pre>
172 737
173</body> 738</body>
174</section> 739</section>
175</chapter> 740</chapter>
741
176<chapter> 742<chapter>
177<title>Configuring ALSA</title> 743<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> 744<section>
208<section> 745<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> 746<body>
231</section>
232<section>
233<title>Having ALSA Activated at Boot</title>
234<body>
235 747
236<p>
237To activate ALSA support at boot, add the <c>alsasound</c> init script to the
238boot runlevel:
239</p> 748<p>
240 749If your sound card is one of those that come with on-board MIDI synthesizers
241<pre caption="Adding alsasound to the boot runlevel"> 750and you would like to listen to some .mid files, you have to install
242# <i>rc-update add alsasound boot</i> 751<c>awesfx</c> which is basically a set of utilities for controlling the AWE32
243# <i>/etc/init.d/alsasound start</i> 752driver. We need to install it first. If you don't have a hardware synthesizer,
244</pre> 753you can use a virtual one. Please see the section on
245 754<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> 755</p>
253By default, all sound channels are muted. To fix this, run <c>amixer</c>:
254</p>
255 756
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"> 757<pre caption="Installing awesfx">
304# <i>emerge awesfx</i> 758# <i>emerge awesfx</i>
305</pre> 759</pre>
306 760
307<p> 761<note>
308If you have a collection of sound fonts somewhere, place them in 762You 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 763CD or a Windows installation into <path>/usr/share/sounds/sf2/</path>. For
310called <path>8MBGMSFX.SF2</path> or <path>CT4GMSFX.SF2</path>. 764example a sound font file for the Creative SBLive! card would be 8MBGMSFX.SF2.
765</note>
766
311</p> 767<p>
312 768After copying over the Soundfont files, we can then play a midi file as shown.
769You can also add the <c>asfxload</c> command to
770<path>/etc/conf.d/local.start</path>, so that the sound font is loaded
771every time the system starts up.
313<p> 772</p>
314After copying over the sound font, select them using <c>sfxload</c>:
315</p>
316 773
774<note>
775<path>/mnt</path> paths mentioned in the code listing(s) below will <e>not</e>
776be the same in your machine. They are just an example. Please be careful to
777change the path to suit your machine.
778</note>
779
317<pre caption="Loading the sound font"> 780<pre caption="Loading Soundfonts">
781<comment>(First, copy the Soundfont)</comment>
782# <i>cp /mnt/win2k/Program\ Files/CreativeSBLive2k/SFBank/8MBGMSFX.SF2 /usr/share/sounds/sf2/</i>
783<comment>(We load the specific Soundfont)</comment>
318# <i>sfxload /usr/share/sfbank/8MBGMSFX.SF2</i> 784# <i>asfxload /usr/share/sounds/sf2/8MBGMSFX.SF2</i>
319</pre> 785</pre>
320 786
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> 787<p>
325 788You can now play midi files using a program like <c>aplaymidi</c>. Run
789<c>aplaymidi -l</c> to get a list of available ports and then pick one
790to play the file on.
326<p> 791</p>
327If you can't find soundfonts on your driver CD you can download some online from 792
328<uri>http://www.parabola.demon.co.uk/alsa/awe64.html</uri>. 793<pre caption="Playing MIDI">
794<comment>(Check open ports)</comment>
795# <i>aplaymidi -l</i>
796 Port Client name Port name
797 64:0 EMU10K1 MPU-401 (UART) EMU10K1 MPU-401 (UART)
798 65:0 Emu10k1 WaveTable Emu10k1 Port 0
799 65:1 Emu10k1 WaveTable Emu10k1 Port 1
800 65:2 Emu10k1 WaveTable Emu10k1 Port 2
801 65:3 Emu10k1 WaveTable Emu10k1 Port 3
802<comment>(Pick a port, and play a mid file)</comment>
803# <i> aplaymidi --port=65:0 /mnt/shyam/music/midi/mi2.mid</i>
329</p> 804</pre>
330 805
331</body> 806</body>
332</section>
333<section> 807</section>
808<section id="vsynth">
334<title>Timidity++ Virtual Synthesizer</title> 809<title>Virtual Synthesizers</title>
335<body> 810<body>
336 811
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> 812<p>
813If your sound card lacks a hardware synthesizer, you could use a virtual one
814like <c>timidity++</c>. Installation is a breeze.
815</p>
342 816
343<pre caption="Installing Timidity++"> 817<pre caption="Installing timidity++">
344# <i>emerge timidity++</i> 818# <i>emerge timidity++</i>
345</pre> 819</pre>
346 820
347<p> 821<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, 822For 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. 823install <c>timidity-eawpatches</c> or <c>timidity-shompatches</c> which will
824give you some sound fonts. You can have multiple sound font configurations
825installed, and you can place your own in <path>/usr/share/timidity/</path>.
826To switch between different timidity configurations, you should use the
827<c>timidity-update</c> tool provided in the timidity++ package.
360</p> 828</p>
361 829
362<pre caption="Installing timidity-eawpatches"> 830<pre caption="Installing sound fonts">
363# <i>emerge timidity-eawpatches</i> 831# <i>emerge timidity-eawpatches</i>
832# <i>timidity-update -g -s eawpatches</i>
833
834<comment>(or)</comment>
835
836# <i>emerge timidity-shompatches</i>
837# <i>timidity-update -g -s shompatches</i>
364</pre> 838</pre>
365 839
366<p> 840<p>
367Don't forget to add <c>timidity</c> to the default runlevel. 841Don't forget to add <c>timidity</c> to the default runlevel.
368</p> 842</p>
370<pre caption="Adding timidity to the default runlevel"> 844<pre caption="Adding timidity to the default runlevel">
371# <i>rc-update add timidity default</i> 845# <i>rc-update add timidity default</i>
372# <i>/etc/init.d/timidity start</i> 846# <i>/etc/init.d/timidity start</i>
373</pre> 847</pre>
374 848
849<p>
850You can now try out <uri link="#doc_chap4_pre3">Playing MIDI</uri> files.
851</p>
852
375</body> 853</body>
376</section>
377<section> 854</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> 855<section>
413<title>Tools and Firmware</title> 856<title>Tools and Firmware</title>
414<body> 857<body>
415 858
416<p> 859<p>
423<pre caption="Selecting ALSA Tools in /etc/make.conf"> 866<pre caption="Selecting ALSA Tools in /etc/make.conf">
424ALSA_TOOLS="as10k1 ac3dec" 867ALSA_TOOLS="as10k1 ac3dec"
425</pre> 868</pre>
426 869
427<p> 870<p>
871If 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): 872Now, install the <c>alsa-tools</c> (and/or <c>alsa-firmware</c>) package(s):
429</p> 873</p>
430 874
431<pre caption="Installing ALSA Tools"> 875<pre caption="Installing ALSA Tools">
432# <i>emerge alsa-tools</i> 876# <i>emerge alsa-tools</i>
433</pre> 877</pre>
434 878
435</body> 879</body>
436</section> 880</section>
437<section> 881<section>
438<title>Activating Joystick Support</title> 882<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> 883<body>
482</section> 884
885<p>
886Everyone who contributed to the earlier version of the Gentoo ALSA Guide:
887Vincent Verleye, Grant Goodyear, Arcady Genkin, Jeremy Huddleston,
888John P. Davis, Sven Vermeulen, Benny Chuang, Tiemo Kieft and Erwin.
889</p>
890
891</body>
483<section> 892</section>
893<section>
484<title>Resources</title> 894<title>References</title>
485<body> 895<body>
486 896
487<ul> 897<ul>
488 <li><uri link="http://www.alsa-project.org">The ALSA Project</uri></li> 898 <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> 899 <li><uri link="http://linux-sound.org">Linux Sound/MIDI Software</uri></li>
491</ul> 900</ul>
492 901
493</body> 902</body>
494</section> 903</section>

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