why does my stream sound so bad?

[stinkpot]

hi all,

i've been happily using slimserver for years now, up until i played a stream on my laptop which was hooked up to my fancy-pants speakers. my music sounded horrible: there was all of this static and white noise, especially during quiet sections of music.

at first, i attributed this to the nature of streaming music at ~30-40kbps; however, it occurred to me that when i stream music in itunes on the laptop (from another computer), the music sounds almost like the CD.

i'd love to hear any potential solutions or advice!

oh, and my setup:

*slimserver 6.2.1 (i know, i know, i should upgrade ...)
*player quality set to 0
*i believe the decoding is being done by LAME
*server is a debian box
*stream is being played on itunes

thanks again!
- lawrence

[snarlydwarf]

Why would you stream at 40kbps? It would only do that if you either had 40kbps files or if for some reason you used bitrate limiting...

I assume you're using stream.mp3: again, unless you transcode, that is returning exactly what is in a given mp3 so it really sounds like you are transcoding to 40kbps for some reason.

[stinkpot]

Why would you stream at 40kbps? It would only do that if you either had 40kbps files or if for some reason you used bitrate limiting...

I assume you're using stream.mp3: again, unless you transcode, that is returning exactly what is in a given mp3 so it really sounds like you are transcoding to 40kbps for some reason.

my apologies, i meant the stream is passing at ~40KB/s (= 320 kbps)!

[snarlydwarf]

What format is the original? You said:

i believe the decoding is being done by LAME

But LAME is an encoder: it takes pcm data (ie, "WAV") and converts to mp3. Is the file MP3? Or is it something else being transcoded to mp3?

[JJZolx]

i've been happily using slimserver for years now, up until i played a stream on my laptop which was hooked up to my fancy-pants speakers. my music sounded horrible: there was all of this static and white noise, especially during quiet sections of music.

at first, i attributed this to the nature of streaming music at ~30-40kbps; however, it occurred to me that when i stream music in itunes on the laptop (from another computer), the music sounds almost like the CD.

i'd love to hear any potential solutions or advice!

oh, and my setup:

*slimserver 6.2.1 (i know, i know, i should upgrade ...)
*player quality set to 0
*i believe the decoding is being done by LAME
*server is a debian box
*stream is being played on itunes

Are you talking about connecting to SlimServer's stream.mp3 and playing that back through the laptop? How were you listening before hooking up the laptop to your sound system?

[stinkpot]

What format is the original? You said:



But LAME is an encoder: it takes pcm data (ie, "WAV") and converts to mp3. Is the file MP3? Or is it something else being transcoded to mp3?

sorry, i'm not too up on mp3 encoding/decoding.

that's a good point though - i just realized that the problem appears to be localized to playback of apple aac files.

slimserver says it uses faad/lame to decode the aac files and stream them to mp3.

if this helps, i've found this line that i added a long time ago to my convert.conf file:

mov mp3 * *
[faad] -w -f 2 $FILE$ | [lame] --resample 44100 --silent -q $QUALITY$ -b $BITRATE$ -r - -

[stinkpot]

Are you talking about connecting to SlimServer's stream.mp3 and playing that back through the laptop? How were you listening before hooking up the laptop to your sound system?

the laptop has a copy of the song stored on its hard drive.

[stinkpot]

hmm, maybe this is what's going on ...

http://forums.slimdevices.com/showthread.php?t=18219

[stinkpot]

indeed, it was a faad problem!

i followed the great walkthrough here:
http://forums.slimdevices.com/showth...t=18219&page=8

and added a "-x" to my convert.conf aac entry:
mov mp3 * *
[faad] -w -f 2 $FILE$ | [lame] --resample 44100 -x --silent -q $QUALITY$ -b $BITRATE$ -r - -

and voila, beautiful music. hooray!

thanks guys.