[linux-audio-user] Sound cards inquiry (onboard solutions).

[Gain Paolo Mureddu]

Hello list, I know my inquiry is more suited for the ALSA list, but I 
thought I would ask you guys here first (more like the users, than users 
having issues with drivers).

Well, the thing is that I would like to know which "embedded" audio 
solutions, in your experience provide the best set of features? Let me 
explain, I am conducting a research on Linux for the average user on 
commodity hardware. The thing is that for some tasks, the embedded audio 
solutions, simply won't "cut it", particularly for VoIP applications 
which are gaining strength and the overall multimedia experience. To 
this end, we all know audio plays a key role. However right now on Linux 
there is a big problem: A mixed audio environment. Why do I say this? 
well, on one hand we've got the incredible efforts made by the good 
folks over at the ALSA project, an on the other hand, we've got the 
number of applications that still use the Open Sound System for 
compatibility with other Unix systems. This is not a bad thing, the 
problem, in my experience, is that as a general rule commodity hardware 
(i.e motherboard embedded audio solutions) do not, at large, support 
hardware mixing with the ALSA drivers. This is a problem, because in the 
mixed environment with ALSA drivers, and OSS applications it is simply 
next to impossible to have proper software mixing. ALSA can do soft mix, 
but it can do so with applications which "talk" ALSA. Fortunately ALSA 
can decode OSS applications' audio calls, but can't soft mix the 
streams. This is the problem (IMO a big problem) for the average user 
who may want to play a game of supertux while talking with mom in Ekiga, 
and having some music in the background while keeping the game's SFX. 
These are not uncommon scenarios any more.

So, if a user asks what components would he have to buy in oder of being 
able to experience all these sound-rich environments with Linux, or a 
user who may be in the hunt for components for a new Linux PC with 
commodity hardware that would do the job; which embedded solutions 
support hardware mixing with ALSA in Linux?

I know the obvious answer is "Go check the ALSA sound card matrix", but 
here's a problem: which chipsets are actually used for motherboard audio 
solutions and which are used for separate cards? I know a plethora of 
users have opted to some solutions like running two cards, the embedded 
and a cheap add-on card, or stuff like that, while others are lucky to 
have, say a VIA VT8235/37 southbridge based motherboard with an audio 
controller, which supports up to 4 channels (voices/devices) in 
hardware, or some others are even luckier and have one of the rare 
4DWave based audio solutions (which support as much as 32 
channels/voices/devices). I know some chipsets like ALi and VIA 
(VT8235/37) support hardware mixing, but there might be a problem: the 
offering of VIA based motherboards is not that great anymore ever since 
ATi and nVidia started playing SLI/Crossfire, and as such have flooded 
the market with these boards, which include an ALC audio codec or the 
atiixp controller which both do not support hardware mixing (in my 
experience, anyway, things might have changed). The majority of audio 
solutions "in the wild" use the snd-intel8x0 driver which to the best of 
my knowledge does not support hardware mixing or the chips used with it 
do not support it.

Given the mixed audio environment in Linux, and hence the lack of 
ability to successfully soft mix with either drivers (ALSA/OSS) while 
using an application written for the other, is why in my opinion, 
hardware mixing is a must for Linux for the average user as it stands 
today. I realize this will slowly change overtime as even more 
abstractions are made available to make this transparent across Unix 
systems (like the use of Gstreamer as the platform-dependant sound 
backend) and the audio system, applications and drivers used will no 
longer be a problem, but in the mean time, a great deal of users who 
want to use Linux experience some problems that for some may not be 
showstoppers, but for others they deffinitely are.

By the way, I asked first here, to gather *user* information, rather 
than developers, as different users usually have different experiences 
with the same or similar hardware.

I am so terribly sorry if this is completely off-topic in the list and 
if the e-mail is too large.