Sound Updates For Linux 3.20 Improve HP Laptops, Other Features

[Zan Lynx]

I know a lot of folks are going to disagree with me, but I don't like alsa. Yeah, sure you get sound, but that's not good enough. I can see putting audio codec drivers in the kernel, but the sound system really needs to be in userspace.

The second major problem is the alsa interface is only exposed to userspace by a device sink. There is -no- userspace service.

OK, so you can see why I am confused by what you say. First you want only the basic drivers in the kernel, and the sound system in user space.

What you seem to be missing here is that PulseAudio is exactly the userspace sound layer that you wanted. It offers the mixing, the per application audio levels, the PCM reclocking from 44 to 48 KHz, etc.

ALSA is the low level hardware. And yes, if you go below ALSA's library interface, every device looks different. That's really the only choice that makes sense though. If you make every device look the same then you can't use it properly. You end up putting stuff in the kernel to convert audio formats. With integer math and lookup tables. And what, make everything look like an identical 5.1 or 7.2 output with one microphone and one line input?

You know there's a reason JACK and the Linux pro-audio stuff likes ALSA. It's because it's the only reasonable way to handle a 24 channel card. OSS couldn't cut it.

[duby229]

OK, so you can see why I am confused by what you say. First you want only the basic drivers in the kernel, and the sound system in user space.

What you seem to be missing here is that PulseAudio is exactly the userspace sound layer that you wanted. It offers the mixing, the per application audio levels, the PCM reclocking from 44 to 48 KHz, etc.

ALSA is the low level hardware. And yes, if you go below ALSA's library interface, every device looks different. That's really the only choice that makes sense though. If you make every device look the same then you can't use it properly. You end up putting stuff in the kernel to convert audio formats. With integer math and lookup tables. And what, make everything look like an identical 5.1 or 7.2 output with one microphone and one line input?

You know there's a reason JACK and the Linux pro-audio stuff likes ALSA. It's because it's the only reasonable way to handle a 24 channel card. OSS couldn't cut it.

I'm not saying that alsa doesn't have some good drivers, yeah it does. The problem is that some of the best alsa drivers don't work well or at all with Pulse Audio because they don't all expose exactly the same standardized interface. One of the few drivers that works decently with PA is the HDA driver. They put all the AC97 supporting chipsets into a single monolithic driver in an attempt to hide that fact. That alleviates the problem for a lot of people because that driver supports their sound chipset. But it doesn't fix the problem.

Fundamentally speaking, I don't have a problem with Pulse Audio. But as long as it runs on top of alsa, it isn't a solution, it's only a band aid.

[duby229]

oops double post

[duby229]

I'm not saying that alsa doesn't have some good drivers, yeah it does. The problem is that some of the best alsa drivers don't work well or at all with Pulse Audio because they don't all expose exactly the same standardized interface. One of the few drivers that works decently with PA is the HDA driver. They put all the AC97 supporting chipsets into a single monolithic driver in an attempt to hide that fact. That alleviates the problem for a lot of people because that driver supports their sound chipset. But it doesn't fix the problem.

Fundamentally speaking, I don't have a problem with Pulse Audio. But as long as it runs on top of alsa, it isn't a solution, it's only a band aid.

EDIT: I use a C-Media 8770 and that driver has fantastic alsa support. It's absolutely fabulous. But I get serious problems in PA every time I've broken down to try it. I get serious glitches caused by latency in the sound, and that comes along with stupid high cpu usage.

Yeah, I blame Pulse Audio, but really it's alsa's fault. Alsa needs standardized interface that all drivers need to respect. It doesn't.

If a new sound interface ever gets developed, then a new sound service should be developed at the same time.

[Kano]

Do you use a 10y old CPU or what do you call high CPU usage? Show me htop.