Re: [Libcdio-help] cdda-player: no sound/music

[Rocky Bernstein]

On Mon, Mar 14, 2011 at 5:14 PM, Ralf Eichinger
<address@hidden> wrote:
> I installed libcdio-utils 0.81-4 under Ubuntu 10.10.
> I wanted to play a music cd by calling cdda-player.
> It starts, the seconds are counted up,

If there is an activity light on the drive, that lights up too? RIght?

> but no sound to hear.
> alsamixer shows volume set to full.
> xine plays it without problems, user is in group audio and cdrom.
> ...
> What is the problem?
> Has it problems with alsa?

No. Alsa is not involved here.

There are two modes in which one can play a CD. In the mode used by
cd-player the circuitry of the drive to produce get sound from. If
there an activity light and that's on and there is a headphone jack,
if you plug in headphones into the jack, then I think you will here
the CD playing. Older drives also used to have a volume knob and on
the drive and that was used to control volume as well. Sometimes there
were other buttons like eject and change tracks.

If this is a computer where you can open the computer up, often there
is what I think is called an "analog" cable connection that one can
hook up from the drive to some place on the motherboard.

The other mode, which xine and alsa use, read the sectors data from
the CD and then use that digital data with their own digital to analog
circuitry. It is here where Alsa gets involved to do mixing, routing,
volume control and so on. The cd-paranoia mode also uses this
data-reading mode (rather than issuing a "play" command to the drive)
since it tries to verify and correct the data in the presence of
scratches.

A feature of that older mode used by cd-player is that there are no
CPU resources used when you play a CD. In fact your computer can
completely hang and the CD will continue to play.

In some sense cd-player was written just to test and show off that
kind of mode that CD drives had.


>
> Please help, because I want to use the library for programming an own
> little cd-player...
>
>
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