<html>
<head>
<meta content="text/html; charset=UTF-8" http-equiv="Content-Type">
</head>
<body text="#000000" bgcolor="#FFFFFF">
On 12/22/2015 06:57 PM, Todd Millecam wrote:<br>
<blockquote
cite="mid:CAJWhT3f+LXok6UG+0S7_Vk-CaELrxvdeAJXA2wVv6U-vzV-tAQ@mail.gmail.com"
type="cite">
<div>
<div><br>
</div>
In the case of sound, the general chain goes as follows:<br>
<br>
</div>
kernel->pci or usb bus->udev rules -> alsa or pulse ->
ubuntu config and application<br>
</blockquote>
<br>
You have this slightly wrong. ALSA is the the drivers for the
actual soundcard. Pulseaudio is an advanced sound server that sits
on top of ALSA to provide extra functionality, like mixing multiple
channels of audio together, and per application volume control, that
ALSA doesn't have. Pulse then exports out it's own ALSA connection
so that programs that don't know how to talk to pulse can still make
sound.<br>
<br>
ALSA only programs would do:<br>
<meta http-equiv="content-type" content="text/html; charset=UTF-8">
<b><span style="color: rgb(37, 37, 37); font-family: sans-serif;
font-size: 14px; font-style: normal; font-variant: normal;
font-weight: normal; letter-spacing: normal; line-height:
22.4px; orphans: auto; text-align: start; text-indent: 0px;
text-transform: none; white-space: normal; widows: 1;
word-spacing: 0px; -webkit-text-stroke-width: 0px; display:
inline !important; float: none; background-color: rgb(255, 255,
255);">Sound source -> libALSA -> PulseAudio -><span
class="Apple-converted-space"> </span></span></b><span
style="color: rgb(37, 37, 37); font-family: sans-serif; font-size:
14px; font-style: normal; font-variant: normal; letter-spacing:
normal; line-height: 22.4px; orphans: auto; text-align: start;
text-indent: 0px; text-transform: none; white-space: normal;
widows: 1; word-spacing: 0px; -webkit-text-stroke-width: 0px;
background-color: rgb(255, 255, 255);">ALSA driver</span><span
style="color: rgb(37, 37, 37); font-family: sans-serif; font-size:
14px; font-style: normal; font-variant: normal; font-weight:
normal; letter-spacing: normal; line-height: 22.4px; orphans:
auto; text-align: start; text-indent: 0px; text-transform: none;
white-space: normal; widows: 1; word-spacing: 0px;
-webkit-text-stroke-width: 0px; display: inline !important; float:
none; background-color: rgb(255, 255, 255);"><b><span
class="Apple-converted-space"> </span></b><span
class="Apple-converted-space"></span>-> hardware<br>
</span><br>
While pulse programs would do:<br>
<meta http-equiv="content-type" content="text/html; charset=UTF-8">
<b><i><span style="color: rgb(37, 37, 37); font-family: sans-serif;
font-size: 14px; font-style: normal; font-variant: normal;
font-weight: normal; letter-spacing: normal; line-height:
22.4px; orphans: auto; text-align: start; text-indent: 0px;
text-transform: none; white-space: normal; widows: 1;
word-spacing: 0px; -webkit-text-stroke-width: 0px; display:
inline !important; float: none; background-color: rgb(255,
255, 255);">Sound source<i> -></i> PulseAudio <i>-></i><span
class="Apple-converted-space"> </span></span></i></b><i><span
style="color: rgb(37, 37, 37); font-family: sans-serif;
font-size: 14px; font-style: normal; font-variant: normal;
font-weight: normal; letter-spacing: normal; line-height:
22.4px; orphans: auto; text-align: start; text-indent: 0px;
text-transform: none; white-space: normal; widows: 1;
word-spacing: 0px; -webkit-text-stroke-width: 0px; display:
inline !important; float: none; background-color: rgb(255, 255,
255);"><span class="Apple-converted-space"></span></span></i><i><span
style="color: rgb(37, 37, 37); font-family: sans-serif;
font-size: 14px; font-style: normal; font-variant: normal;
font-weight: normal; letter-spacing: normal; line-height:
22.4px; orphans: auto; text-align: start; text-indent: 0px;
text-transform: none; white-space: normal; widows: 1;
word-spacing: 0px; -webkit-text-stroke-width: 0px; display:
inline !important; float: none; background-color: rgb(255, 255,
255);"><span class="Apple-converted-space"></span></span></i><i><span
style="color: rgb(37, 37, 37); font-family: sans-serif;
font-size: 14px; font-style: normal; font-variant: normal;
letter-spacing: normal; line-height: 22.4px; orphans: auto;
text-align: start; text-indent: 0px; text-transform: none;
white-space: normal; widows: 1; word-spacing: 0px;
-webkit-text-stroke-width: 0px; background-color: rgb(255, 255,
255);">ALSA driver</span></i><i><span style="color: rgb(37, 37,
37); font-family: sans-serif; font-size: 14px; font-style:
normal; font-variant: normal; font-weight: normal;
letter-spacing: normal; line-height: 22.4px; orphans: auto;
text-align: start; text-indent: 0px; text-transform: none;
white-space: normal; widows: 1; word-spacing: 0px;
-webkit-text-stroke-width: 0px; display: inline !important;
float: none; background-color: rgb(255, 255, 255);"><span
class="Apple-converted-space"></span></span></i><i><span
style="color: rgb(37, 37, 37); font-family: sans-serif;
font-size: 14px; font-style: normal; font-variant: normal;
font-weight: normal; letter-spacing: normal; line-height:
22.4px; orphans: auto; text-align: start; text-indent: 0px;
text-transform: none; white-space: normal; widows: 1;
word-spacing: 0px; -webkit-text-stroke-width: 0px; display:
inline !important; float: none; background-color: rgb(255, 255,
255);"><span class="Apple-converted-space"></span></span></i><b><i><span
style="color: rgb(37, 37, 37); font-family: sans-serif;
font-size: 14px; font-style: normal; font-variant: normal;
font-weight: normal; letter-spacing: normal; line-height:
22.4px; orphans: auto; text-align: start; text-indent: 0px;
text-transform: none; white-space: normal; widows: 1;
word-spacing: 0px; -webkit-text-stroke-width: 0px; display:
inline !important; float: none; background-color: rgb(255,
255, 255);"><span class="Apple-converted-space"> </span><i>-></i>
Hardware</span></i></b><br>
<meta http-equiv="content-type" content="text/html; charset=UTF-8">
<span style="color: rgb(37, 37, 37); font-family: sans-serif;
font-size: 14px; font-style: normal; font-variant: normal;
font-weight: normal; letter-spacing: normal; line-height: 22.4px;
orphans: auto; text-align: start; text-indent: 0px;
text-transform: none; white-space: normal; widows: 1;
word-spacing: 0px; -webkit-text-stroke-width: 0px; display: inline
!important; float: none; background-color: rgb(255, 255, 255);"><br>
Pre-pulse was rather grim times for audio with many programs
grabbing the audio card exclusively so that nothing else would be
able to make sounds.<br>
<br>
Brian Cluff<br>
<br>
</span>
</body>
</html>