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Steven Kramer
2004-02-10, 12:15
discuss-bounces (AT) lists (DOT) slimdevices.com wrote:
> Quoting Steven Kramer <stevek1050pub (AT) comcast (DOT) net>:
>
>> I know this was a problem that was suppose to have been addressed,
>> but I am still having it. When using the Squeezebox digital output
>> (either optical or coax), the beginning of songs is being cutoff.
>> Analog output does not have this problem, but of course, I would
>> prefer to use the digital output since it sounds much better.
>>
>> I am running Version 5.1 (last official download) on WinXP home with
>> a
>> 1.4GHz Athlon processor and 512 meg of memory.
>>
>
> just for confirmation, did you press and hold BRIGHTNESS to update
> the firmware that came with this release? If you have used recently
> nightlies and upgraded to one of the interim firmwares, the
> squeezebox would not report the need to upgrade. During development
> stages, the firmware was changed, but the release level was not.
>
Yes, I did hold the brightness to update and was told that the update was
successful. Player settings indicate I have Firmware Version 7.

--Steve
-------------------------------------
Steven Kramer
stevek1006 (AT) comcast (DOT) net
-------------------------------------

seanadams
2004-02-10, 13:36
This is a known issue with mp3 and will be fixed. Sorry it's taking so
long...


On Feb 10, 2004, at 11:15 AM, Steven Kramer wrote:

> discuss-bounces (AT) lists (DOT) slimdevices.com wrote:
>> Quoting Steven Kramer <stevek1050pub (AT) comcast (DOT) net>:
>>
>>> I know this was a problem that was suppose to have been addressed,
>>> but I am still having it. When using the Squeezebox digital output
>>> (either optical or coax), the beginning of songs is being cutoff.
>>> Analog output does not have this problem, but of course, I would
>>> prefer to use the digital output since it sounds much better.
>>>
>>> I am running Version 5.1 (last official download) on WinXP home with
>>> a
>>> 1.4GHz Athlon processor and 512 meg of memory.
>>>
>>
>> just for confirmation, did you press and hold BRIGHTNESS to update
>> the firmware that came with this release? If you have used recently
>> nightlies and upgraded to one of the interim firmwares, the
>> squeezebox would not report the need to upgrade. During development
>> stages, the firmware was changed, but the release level was not.
>>
> Yes, I did hold the brightness to update and was told that the update
> was
> successful. Player settings indicate I have Firmware Version 7.
>
> --Steve
> -------------------------------------
> Steven Kramer
> stevek1006 (AT) comcast (DOT) net
> -------------------------------------
>
>
>

Stuart
2004-02-10, 15:28
Since updating to v5.1 & v7, files recorded at a sample rate of 48k
sound as if they have been slowed down. Anyone else experiencing this?

Roy M. Silvernail
2004-02-10, 16:04
On Tue, 2004-02-10 at 17:28, Stuart wrote:
> Since updating to v5.1 & v7, files recorded at a sample rate of 48k
> sound as if they have been slowed down. Anyone else experiencing this?

What type of files? Squeezebox forces all streams to 44.1 kHz (bug
128), so the only way a 48 kHz stream would have sounded right is if
there were resampling in the pipe somewhere. Have you checked your
convert.conf for changes that would affect resampling?
--
Roy M. Silvernail is roy (AT) rant-central (DOT) com, and you're not
Never Forget: It's Only 1's and 0's!
SpamAssassin->procmail->/dev/null->bliss
http://www.rant-central.com

Stuart
2004-02-11, 03:25
>>Since updating to v5.1 & v7, files recorded at a sample rate of 48k
>>sound as if they have been slowed down. Anyone else experiencing this?
>
>
> What type of files? Squeezebox forces all streams to 44.1 kHz (bug
> 128), so the only way a 48 kHz stream would have sounded right is if
> there were resampling in the pipe somewhere. Have you checked your
> convert.conf for changes that would affect resampling?

I am playing mp2 files @ 48k

In my convert.conf I have

mp2 mp3 squeezebox *
$lame$ --silent --mp2input -b $BITRATE$ $FILES$ -

Stuart.

Roy M. Silvernail
2004-02-11, 04:53
On Wed, 2004-02-11 at 05:25, Stuart wrote:
> >>Since updating to v5.1 & v7, files recorded at a sample rate of 48k
> >>sound as if they have been slowed down. Anyone else experiencing this?
> >
> >
> > What type of files? Squeezebox forces all streams to 44.1 kHz (bug
> > 128), so the only way a 48 kHz stream would have sounded right is if
> > there were resampling in the pipe somewhere. Have you checked your
> > convert.conf for changes that would affect resampling?
>
> I am playing mp2 files @ 48k
>
> In my convert.conf I have
>
> mp2 mp3 squeezebox *
> $lame$ --silent --mp2input -b $BITRATE$ $FILES$ -

That looks reasonable. Can you send me a 48k mp2 file to test locally?
Contact me offlist for an ftp site to upload to.
--
Roy M. Silvernail is roy (AT) rant-central (DOT) com, and you're not
Never Forget: It's Only 1's and 0's!
SpamAssassin->procmail->/dev/null->bliss
http://www.rant-central.com

Stuart
2004-02-11, 08:31
>>
>>In my convert.conf I have
>>
>>mp2 mp3 squeezebox *
>> $lame$ --silent --mp2input -b $BITRATE$ $FILES$ -
>
>
> That looks reasonable. Can you send me a 48k mp2 file to test locally?
> Contact me offlist for an ftp site to upload to.

It seems to be any file @ 48k, not just mp2 (I just did a test with a
..wav file made with CoolEdit). You say Squeezebox forces everything to
44.1k? So does it automatically resample everything?

I'll do some more scientific tests later to make sure I'm not hearing
things. It's a subtle shift in pitch which I noticed while listening to
familiar voices on the radio.

Stuart.

Roy M. Silvernail
2004-02-11, 09:10
Stuart said:
>>>
>>>In my convert.conf I have
>>>
>>>mp2 mp3 squeezebox *
>>> $lame$ --silent --mp2input -b $BITRATE$ $FILES$ -
>>
>>
>> That looks reasonable. Can you send me a 48k mp2 file to test locally?
>> Contact me offlist for an ftp site to upload to.
>
> It seems to be any file @ 48k, not just mp2 (I just did a test with a
> .wav file made with CoolEdit). You say Squeezebox forces everything to
> 44.1k? So does it automatically resample everything?

No, it simply assumes that the incoming stream is 44.1k, so streams that
aren't get pitch-shifted. I noticed when I tried playing an oddball ogg
file that is 22.05k. Oggdec dumps it out as raw PCM and I get the
Chipmunks. I've since settled on using sox for most of my transcoding and
I explicitly set a resample rate.
--
Roy M. Silvernail is roy (AT) rant-central (DOT) com, and you're not
http://www.rant-central.com is the new scytale
Never Forget: It's Only 1's and 0's!
SpamAssassin->procmail->/dev/null->bliss

seanadams
2004-02-11, 09:39
For PCM streaming, the server only knows about 44.1KHz right now. For
mp3/mp2, all possible sample rates are automatically detected in the
stream. The hardware is ready to do 48KHz PCM and other sample rates
and it's just one command in the initialization sequence to change the
rate. Just need to add the support for these - probably will need some
new syntax in convert.conf

I'm not sure though why that lame command is not working correctly
though. Seems to me it should leave the sample rate as-is, and 48khz
mp3 works fine to my knowledge. I think I missed the background on this
though... why won't the mp2 play directly?

On Feb 11, 2004, at 8:10 AM, Roy M. Silvernail wrote:

>
> Stuart said:
>>>>
>>>> In my convert.conf I have
>>>>
>>>> mp2 mp3 squeezebox *
>>>> $lame$ --silent --mp2input -b $BITRATE$ $FILES$ -
>>>
>>>
>>> That looks reasonable. Can you send me a 48k mp2 file to test
>>> locally?
>>> Contact me offlist for an ftp site to upload to.
>>
>> It seems to be any file @ 48k, not just mp2 (I just did a test with a
>> .wav file made with CoolEdit). You say Squeezebox forces everything to
>> 44.1k? So does it automatically resample everything?
>
> No, it simply assumes that the incoming stream is 44.1k, so streams
> that
> aren't get pitch-shifted. I noticed when I tried playing an oddball
> ogg
> file that is 22.05k. Oggdec dumps it out as raw PCM and I get the
> Chipmunks. I've since settled on using sox for most of my transcoding
> and
> I explicitly set a resample rate.
> --
> Roy M. Silvernail is roy (AT) rant-central (DOT) com, and you're not
> http://www.rant-central.com is the new scytale
> Never Forget: It's Only 1's and 0's!
> SpamAssassin->procmail->/dev/null->bliss
>
>

Stuart
2004-02-11, 09:50
> For PCM streaming, the server only knows about 44.1KHz right now. For
> mp3/mp2, all possible sample rates are automatically detected in the
> stream. The hardware is ready to do 48KHz PCM and other sample rates and
> it's just one command in the initialization sequence to change the
> rate. Just need to add the support for these - probably will need some
> new syntax in convert.conf
>
> I'm not sure though why that lame command is not working correctly
> though. Seems to me it should leave the sample rate as-is, and 48khz mp3
> works fine to my knowledge. I think I missed the background on this
> though... why won't the mp2 play directly?


Thanks for the info Sean. Makes sense to me now, although I'm puzzled
as to why my $lame$ command doesn't seem to work as it did. I'll
investigate some more.

The mp2's wont play directly because they sound choppy. I think you have
a copy of my BBC6.mp2 file I sent Dean last week (if not I can send it).

Stuart.

Stuart
2004-02-13, 13:38
Sean Adams wrote:

>
> For PCM streaming, the server only knows about 44.1KHz right now. For
> mp3/mp2, all possible sample rates are automatically detected in the
> stream.

I just ran a test, and it seems mp2/mp3's sample rates are not being
detected (at least not on my setup). I have two examples here.

www.stu.org.uk/electric480.mp3
www.stu.org.uk/electric441.mp3

If I play these files on my Squeezebox, they sound different. Play them
in Winamp, and they sound fine.

Stuart.