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Frank Xavier Ledo
2005-04-10, 20:28
I recently purchased a used SB1 from a coworker upgraded to an SB2.

Since purchasing it I have tried and failed to get SlimServer running on
Linux to play Apple Lossless files. I tried FAAD (various versions as
suggested by many sources) and got nowhere fast (could not find stream in
.... blah blah blah).

Today on a whim I did yet another Google search and found this:

http://crazney.net/programs/itunes/alac.html

Worked on the first try.

I am having a couple issues though that maybe somebody could help with:

First, It seems that all songs start out with a pop. I am guessing that
the command line options I set in convert.conf were incorrect and are
resulting in a linefeed or space at the start of the song.

What I used is:
mov wav squeezebox *
[alac] $FILE$

As a test I tried using alac to convert the file from *.m4a to *.wav, and
added the wav file to my playlist. There were no pops.

Second, alac supports PCM output. Is there any benefit to using this
instead of wav output?

Thanks in advance for any advice on the above issues. I hope someone who
was looking for a decoder for Apple Lossless finds this useful.

--

Phil Karn
2005-05-07, 16:25
Frank Xavier Ledo wrote:

> First, It seems that all songs start out with a pop. I am guessing that
> the command line options I set in convert.conf were incorrect and are
> resulting in a linefeed or space at the start of the song.
>
> What I used is:
> mov wav squeezebox *
> [alac] $FILE$
>
> As a test I tried using alac to convert the file from *.m4a to *.wav, and
> added the wav file to my playlist. There were no pops.
>
> Second, alac supports PCM output. Is there any benefit to using this
> instead of wav output?

The "pop" is almost certainly the sound of the WAV file header being
misinterpreted as raw PCM audio. Try selecting raw PCM output from alac
and see if the problem goes away.

Are you sure you're using the convert.conf entry you gave above, and
aren't actually transcoding to another format?

In the convert.conf file entries that pipe two codecs together to
transcode from one compressed format to another, the two codecs must
agree on their interchange format. The existing convention *seems* to be
raw little-endian 16-bit stereo PCM *without* a WAV header. If the first
program outputs wav format when the second expects raw PCM, you'll get
the pop.

I'm not exactly sure which native format the Squeezebox 1 expects, WAV
or raw PCM. Anybody know?

--Phil