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Bryce Richards
2004-05-18, 20:01
Got the latest. Works great. Thanks for the resources link.
Found CVS. Built in.

Observation on DAC. I use the spdf line out to a Channel
Islands Audio DAC.

If I power off using the remote while playing from my
collection, the DAC stays locked on-I see the light.

IF I power off while using shoutcast the DAC loses its signal
and the light goes off-that's what I'd expect.

Is anybody else seeing this? What should my DAC do when I
power down the squeezbox?

Thanks,

Bryce.

---- Original message ----
>Date: Tue, 18 May 2004 19:16:40 -0700
>From: kdf <slim-mail (AT) deane-freeman (DOT) com>
>Subject: [slim] some questions
>To: Slim Devices Discussion <discuss (AT) lists (DOT) slimdevices.com>
>
>Today's build has been redone with the fix, so you can
download it again and get
>the fix.
>
>As for cvs, info is at the bottom of this page:
>http://www.slimdevices.com/dev_resources.html
>
>linux, its built in. otherwise you need something like WinCVS.
>
>-kdf
>
>Quoting Bryce Richards <bryce.richards (AT) partingline (DOT) com>:
>
>> Thanks! I'll wait until tomorrow. Don't know how to use CVS.
>> What do I have to do to get access to the slimserver CVS
>> repository, and is there a faq/how-to on getting started w/
it?
>>
>> Thanks again.
>>
>> ---- Original message ----
>> >Date: Tue, 18 May 2004 16:44:48 -0700
>> >From: kdf <slim-mail (AT) deane-freeman (DOT) com>
>> >Subject: [slim] some questions
>> >To: Slim Devices Discussion <discuss (AT) lists (DOT) slimdevices.com>
>> >
>> >Quoting Bryce Richards <bryce.richards (AT) partingline (DOT) com>:
>> >
>> >> kdf,
>> >>
>> >> Which config file stores the 320kbps/No Limit setting?
Every
>> >> time I try to set it to 'No Limit' it flips back to 320.
>> >>
>> >> I'm running slackware-current. Lastest slimserver 5-18.
>> >
>> >its a bug...fixed in CVS now. Will be in tomorrow's build if
>> you don't use cvs
>> >for updates.
>> >
>> >-kdf
>> >
>> >> ---- Original message ----
>> >> >Date: Tue, 18 May 2004 13:01:19 -0700
>> >> >From: kdf <slim-mail (AT) deane-freeman (DOT) com>
>> >> >Subject: [slim] some questions
>> >> >To: Slim Devices Discussion <discuss (AT) lists (DOT) slimdevices.com>
>> >> >
>> >> >Quoting Pat Farrell <pfarrell (AT) pfarrell (DOT) com>:
>> >> >
>> >> >
>> >> >> >I have my Squeezebox connected to a wireless 802.11b
>> >> network. I believe I
>> >> >> >have configured the server so that it doesn't MP3
compress
>> >> data sent to the
>> >> >> >player. The audio drops out every 15 to 30 seconds when
>> >> I'm playing a WAV
>> >> >> >file containing uncompressed CD audio data.
>> >> >>
>> >> >> You need to use wired if you want best sound quality. The
>> >> wireless setup
>> >> >> defaults to compressing on the fly with lame.
>> >> >
>> >> >In recent pre-release builds, and in the upcoming 5.2
>> >> release, Wired will
>> >> >default to Wav and Wireless will default to 320kbps MP3.
>> >> However, there is a
>> >> >player setting for bitrate limiting. You can set this
to "No
>> >> Limit" for your
>> >> >wireless unit, and it will play to ucompressed PCM. If
your
>> >> setup can handle
>> >> >the bandwidth, then you're good to go.
>> >> >
>> >> >-kdf
>> >> >
>> >> >
>> >> >
>> >> >
>> >> >

Pat Farrell
2004-05-18, 20:12
At 11:01 PM 5/18/2004, Bryce Richards wrote:
>Is anybody else seeing this? What should my DAC do when I
>power down the squeezbox?

Kinda depends on your DAC. If you power down the Sqzbx, you are no longer
feeding nice signal. My Benchmark DAC-1 occasionally thinks that's an
error and turns on a really ugly red LED.

I solved that by never powering down the SqueezeBox.
See earlier [slim] BlueSlim thread about dimmers.

Why would you ever turn a Sqzbx off? it doesn't draw any real current.
And it isn't clear if the power brick will stop drawing current even if
the Sqzbx itself is off.

Pat

seanadams
2004-05-19, 12:13
Bryce,

This is the expected behavior. The reason it's like this has to do with
the difference in how our DSP handles the mp3 format (which is framed)
versus raw PCM audio (which is not). For mp3 format, there is a notion
of "sync" ie is there a valid signal present, and this is reflected in
the presence of the s/pdif output signal. But for PCM audio it's
different - the DSP goes into a "passthrough" mode and outputs whatever
it is sent. So in PCM mode, a "null" signal is digital silence, with
the s/pdif output is always active. This ensures that the DAC stays
locked on so that when a new track is started there is no "seam". For
mp3, what we do is send a bit of silence at the beginning, to give the
DAC a little time to lock on to the stream.

Sean


On May 18, 2004, at 8:01 PM, Bryce Richards wrote:

> Got the latest. Works great. Thanks for the resources link.
> Found CVS. Built in.
>
> Observation on DAC. I use the spdf line out to a Channel
> Islands Audio DAC.
>
> If I power off using the remote while playing from my
> collection, the DAC stays locked on-I see the light.
>
> IF I power off while using shoutcast the DAC loses its signal
> and the light goes off-that's what I'd expect.
>
> Is anybody else seeing this? What should my DAC do when I
> power down the squeezbox?
>
> Thanks,
>
> Bryce.
>
> ---- Original message ----
>> Date: Tue, 18 May 2004 19:16:40 -0700
>> From: kdf <slim-mail (AT) deane-freeman (DOT) com>
>> Subject: [slim] some questions
>> To: Slim Devices Discussion <discuss (AT) lists (DOT) slimdevices.com>
>>
>> Today's build has been redone with the fix, so you can
> download it again and get
>> the fix.
>>
>> As for cvs, info is at the bottom of this page:
>> http://www.slimdevices.com/dev_resources.html
>>
>> linux, its built in. otherwise you need something like WinCVS.
>>
>> -kdf
>>
>> Quoting Bryce Richards <bryce.richards (AT) partingline (DOT) com>:
>>
>>> Thanks! I'll wait until tomorrow. Don't know how to use CVS.
>>> What do I have to do to get access to the slimserver CVS
>>> repository, and is there a faq/how-to on getting started w/
> it?
>>>
>>> Thanks again.
>>>
>>> ---- Original message ----
>>>> Date: Tue, 18 May 2004 16:44:48 -0700
>>>> From: kdf <slim-mail (AT) deane-freeman (DOT) com>
>>>> Subject: [slim] some questions
>>>> To: Slim Devices Discussion <discuss (AT) lists (DOT) slimdevices.com>
>>>>
>>>> Quoting Bryce Richards <bryce.richards (AT) partingline (DOT) com>:
>>>>
>>>>> kdf,
>>>>>
>>>>> Which config file stores the 320kbps/No Limit setting?
> Every
>>>>> time I try to set it to 'No Limit' it flips back to 320.
>>>>>
>>>>> I'm running slackware-current. Lastest slimserver 5-18.
>>>>
>>>> its a bug...fixed in CVS now. Will be in tomorrow's build if
>>> you don't use cvs
>>>> for updates.
>>>>
>>>> -kdf
>>>>
>>>>> ---- Original message ----
>>>>>> Date: Tue, 18 May 2004 13:01:19 -0700
>>>>>> From: kdf <slim-mail (AT) deane-freeman (DOT) com>
>>>>>> Subject: [slim] some questions
>>>>>> To: Slim Devices Discussion <discuss (AT) lists (DOT) slimdevices.com>
>>>>>>
>>>>>> Quoting Pat Farrell <pfarrell (AT) pfarrell (DOT) com>:
>>>>>>
>>>>>>
>>>>>>>> I have my Squeezebox connected to a wireless 802.11b
>>>>> network. I believe I
>>>>>>>> have configured the server so that it doesn't MP3
> compress
>>>>> data sent to the
>>>>>>>> player. The audio drops out every 15 to 30 seconds when
>>>>> I'm playing a WAV
>>>>>>>> file containing uncompressed CD audio data.
>>>>>>>
>>>>>>> You need to use wired if you want best sound quality. The
>>>>> wireless setup
>>>>>>> defaults to compressing on the fly with lame.
>>>>>>
>>>>>> In recent pre-release builds, and in the upcoming 5.2
>>>>> release, Wired will
>>>>>> default to Wav and Wireless will default to 320kbps MP3.
>>>>> However, there is a
>>>>>> player setting for bitrate limiting. You can set this
> to "No
>>>>> Limit" for your
>>>>>> wireless unit, and it will play to ucompressed PCM. If
> your
>>>>> setup can handle
>>>>>> the bandwidth, then you're good to go.
>>>>>>
>>>>>> -kdf
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>>

Richard Purdie
2004-05-19, 14:22
Sean Adams:
> This is the expected behavior. The reason it's like this has to do with
> the difference in how our DSP handles the mp3 format (which is framed)
> versus raw PCM audio (which is not). For mp3 format, there is a notion
> of "sync" ie is there a valid signal present, and this is reflected in
> the presence of the s/pdif output signal. But for PCM audio it's
> different - the DSP goes into a "passthrough" mode and outputs whatever
> it is sent. So in PCM mode, a "null" signal is digital silence, with
> the s/pdif output is always active. This ensures that the DAC stays
> locked on so that when a new track is started there is no "seam". For
> mp3, what we do is send a bit of silence at the beginning, to give the
> DAC a little time to lock on to the stream.

Out of interest why not have the system playing silence mp3 frames whenever
there aren't any "proper" mp3 frames to play? That way the receiver lock
should be kept. Changing from PCM to mp3 may still cause a problem though...

--
RP - just curious...