On Tue, Jul 13, 2010 at 08:55:03AM +0200, Jan Stary wrote:
> On Feb 21 14:04:01, Alexandre Ratchov wrote:
> > On Sun, Feb 21, 2010 at 12:29:15AM +0100, Jan Stary wrote:
> > > can people recommend a good uaudio card?
> >
> > It depends on what you want to use it for.
> >
> > I use a m-audio mobilepre for recording and listening music;
> > it's class compliant does 16-bit stereo at 48kHz, and the
> > sound is excellent. It has a stereo preamp and a phantom
> > power, which is handy.
>
> Thank you for the recommendation. I just bought me one,
> and I am very satisfied with the sound.
>
> I disabled the onboard azalia, so that the mobilepre
> becomes audio0. Now the device reports as
>
> uaudio0 at uhub1 port 2 configuration 1 interface 0 "M Audio MobilePre" rev
> 1.10/1.03 addr 2
> uaudio0: audio rev 1.00, 9 mixer controls
> audio0 at uaudio0
>
> Indeed, mixerctl says (using zero configuration,
> that is, no /etc/mixerctl.conf):
>
> inputs.line.mute=on
> inputs.line=0,0
> record.line.mute=off
> record.line=205,205
> inputs.dac.mute=off
> inputs.dac=205,205
> outputs.mix8-i7=0,0
> outputs.spkr.mute=off
> outputs.spkr=230,230
>
> Can you please share your mixerctl output on the Mobile Pre?
>
> I am pleasantly surprised that there are so few controls.
> Last time I saw this was on an old Compaq laptop that has
> just a mic in and line out, and has controls for just that,
> plus the record/master volume.
non-ac97 codec envy(4) have even fewer.
> My current HP laptop doesn't
> really have much more, but has 54 (azalia) controls.
they are useful. probably not to everyone, and probably not to
most people most of the time, but they can be *quite* useful.
> BTW, why is it that the details of mixerctl controls
> are described in azalia(4), which is just one of possible
> audio interfaces? Surely non-azalia devices can be
> mixerctl'ed too, and the control names mean the same,
> right?
for the most part, yes, the description of the controls in azalia(4)
apply to most devices.
why were mixer controls never really documented? dunno, that's
a good question. I suppose it's not really easy, for one thing,
and for another, they should "just make sense". but for them to
"just make sense", you have to know a bit about how the mixer
interface works.
for example, someone was wondering how to make their laptop play
louder at the recent hackathon. I said "you need to increase
inputs.dac", to which was replied, "But that's an input." and
yes, by the name, it sure sounds like an input, like a line input
or a mic input ... but *generally speaking*, mixer control classes
(the first part of a mixer control name, before the first '.'), are
relative to ... the mixer.
a picture is worth a thousand words (or so I've heard):
class | widgets
--------+------------------------------------
inputs | line mic dac beep
| | | | |
| +---+ | | +--+
| | | | |
| +---------+
--------| |the mixer|
| +---------+
| | | |
| master
outputs | | | |
| line hp spkr
|
that's basically what a simple "single mixer" mixer device (essentially
everything pre-azalia) looks like. there may also be a mixer (usually
a much simpler mixer) specifically for recording, and most controls
associated with it will be in the "record" class.
in azalia, you could have multiple mixers, so it gets really hard to
distinguish "input" vs "output", because you could have an output
from one mixer lead to the input of another mixer.
> Also, why is the mixer named 'outputs.mix8-i7' (and not just 'outputs.mix8')?
> What is the i7 'property' (in azalia terms)?
that mean it's "unit 8" of type "mixer" with source terminal "7".
terrible name, but it should be unique, and that's the most important
aspect.
--
jake...@sdf.lonestar.org
SDF Public Access UNIX System - http://sdf.lonestar.org
