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Johnny Stork
2004-12-28, 16:24
I seem to recall a post somewhere, or maybe in docs, that all mp3's are recoded? at some constant bit rate even if they are created at say 320kbps CBR? I just wanted to confirm that any bit rate MP3 or FLAC, will stream at the same rate it was encoded at? I noticed a bit rate limiting option in the menus somewhere, but I want to ensure no re-encoding is done on high bit rate mp3's or FLACS


-----------------------------------------------------
Open Enterprise Solutions
Linux & Open Source Solutions for Business

Johnny Stork
Squamish, BC

www.openenterprise.ca
www.johnnystork.ca

Jules Taplin
2004-12-28, 18:11
Hi Johnny.

The answer to that question is 'It depends'. By default - Wired
Sqeezeboxes are fed the raw data, and Wireless ones are recoded to
320kbps CBR to avoid congesting the link. Those are the settings in your
bitrate limiting options.

And... if you're running an old-style SliMP3 - they only speak mp3, so
FLACs et al will have to be transcoded before they're handed to them.

-- Jules


Johnny Stork wrote:

>I seem to recall a post somewhere, or maybe in docs, that all mp3's are recoded? at some constant bit rate even if they are created at say 320kbps CBR? I just wanted to confirm that any bit rate MP3 or FLAC, will stream at the same rate it was encoded at? I noticed a bit rate limiting option in the menus somewhere, but I want to ensure no re-encoding is done on high bit rate mp3's or FLACS
>
>
>-----------------------------------------------------
>Open Enterprise Solutions
>Linux & Open Source Solutions for Business
>
>Johnny Stork
>Squamish, BC
>
>www.openenterprise.ca
>www.johnnystork.ca
>
>
>

David & Renee MacDonald
2004-12-30, 07:50
I am a little surprised by this comment Jules. Does this mean that my MP3s
are degraded in sound quality if they are recompressed at 320 CBR? Or am I
misunderstanding what you mean by the wireless squeezebox recoding the
songs?

David


----- Original Message -----
From: "Jules Taplin" <slim-discuss (AT) ourhouse (DOT) org.uk>
To: "Slim Devices Discussion" <discuss (AT) lists (DOT) slimdevices.com>
Sent: Tuesday, December 28, 2004 8:11 PM
Subject: [slim] Bit Rates for MP3?


> Hi Johnny.
>
> The answer to that question is 'It depends'. By default - Wired
> Sqeezeboxes are fed the raw data, and Wireless ones are recoded to 320kbps
> CBR to avoid congesting the link. Those are the settings in your bitrate
> limiting options.
>
> And... if you're running an old-style SliMP3 - they only speak mp3, so
> FLACs et al will have to be transcoded before they're handed to them.
>
> -- Jules
>
>
> Johnny Stork wrote:
>
>>I seem to recall a post somewhere, or maybe in docs, that all mp3's are
>>recoded? at some constant bit rate even if they are created at say 320kbps
>>CBR? I just wanted to confirm that any bit rate MP3 or FLAC, will stream
>>at the same rate it was encoded at? I noticed a bit rate limiting option
>>in the menus somewhere, but I want to ensure no re-encoding is done on
>>high bit rate mp3's or FLACS
>>
>>
>>-----------------------------------------------------
>>Open Enterprise Solutions
>>Linux & Open Source Solutions for Business
>>
>>Johnny Stork
>>Squamish, BC
>>
>>www.openenterprise.ca
>>www.johnnystork.ca
>>
>>
>>

Steve Baumgarten
2004-12-30, 08:00
> I am a little surprised by this comment Jules. Does this mean that my MP3s
> are degraded in sound quality if they are recompressed at 320 CBR? Or am I
> misunderstanding what you mean by the wireless squeezebox recoding the
> songs?

MP3 streams are sent as is; all other formats are first decoded to WAV
and then (optionally) converted to 320kbps MP3 streams. The default
behavior is to do the conversion on wireless connections but not on
wired connections; however, you can change the default behavior via a
server setting.

(This is how I have my Squeezebox set up -- it is on a wireless
connection, but it plays uncompressed WAV streams from the server for
all non-MP3 files. This allows me to listen to my FLAC files with full
fidelity.)

SBB





Visit our website at http://www.ubs.com

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thnmnt
2004-12-30, 08:27
i'm a little confused about native formats supported by sb/slim and what
they mean exactly - is this a factor of the sb hardware? or the server
software? for instance, i understand that AAC/MP4 gets converted on the fly
and sends uncompressed files to the sb - which can be problematic with a
wireless setup. is it possible that this and other formats "become native"
in the future? or is it just the nature of the beast that it was designed
for mp3 and everything gets converted to it. sorry if this doesn't make
sense - but i can't really wrap my head around it. i'm not asking for this
so much as just..you know, wondering.

Mike Hartley
2004-12-30, 10:10
Steve,

Here is an e-mail exchange between me and SLIM Support. Read from Bottom
up. Hope it helps.

Mike


Mike,

Well, uncompressed streaming over 802.11b works OK on some networks, but
just doesn't on others. We haven't really found a surefire way to tell if a
particular network will be able to handle it without just trying it... But
if you want to stream uncompressed, wired ethernet or wired ethernet +
802.11g bridge seems to work best.


Regards,
Kevin P.

On Dec 2, 2004, at 11:26 AM, Mike Hartley wrote:


Kevin,
Thanks very much for the reply. I also joined the discussion mailing list
and got some great responses. I'm getting conflicting advice on whether
802.11G is really a requirement for uncompressed streaming. Given that I am
only planning to have one (at most two) SB's in the house and it will be the
only consumer of bandwidth, I'm tempted to try an 802.11b device.
Again, thanks for the info. This looks like a great product.

Mike
----- Original Message -----
From: Kevin Pearsall
To: Mike Hartley
Sent: Thursday, December 02, 2004 1:44 PM
Subject: Compressed vs uncompressed over wireless question before
purchase

Hi Mike,

I'll insert replies below...


I'm am very interested in your product, but I need some clarification on a
few things before I make a purchase. I currently have my music collection
stored on a Windows XP SP2 box coded in WMA lossless format (No DRM used).

My initial plan was to purchase a wireless router and and stream to the
SB. However, there seems to be confusion on some discussion boards
(probably due to lack of research)about how the software handles certain
media formats. My desire is to stream uncompressed and output directly via
the digital out to the digital in of my Yamaha 5790 receiver. Is this
possible with WMA files? I have seen several people that are under the
impression that the Slim-server converts WMA to MP3 compressed and is
actually limited to lower quality 32KHz output even via it's digital out.
Is that correct? If not, can you explain how it would handle this scenario?

So here's the basics on how things work right now with SlimServer:
- WMA (lossless, cbr, vbr, whatever) is uncompressed on the server through
a program called wmadec
- By default it's sent to the Squeezebox uncompressed.
- If bandwidth is an issue and dropouts occur, LAME can be installed to
let SlimServer transcode to MP3 to lower the bandwidth utilization.
- SlimServer does not transcode to MP3 (rather, can not) without LAME
being installed.


Also, since my desire is to end up with the best audio-fidelity possible,
I would entertain the idea of re-rerecording the audio in another format. I
am considering setting up a spare PC as a second dedicated server anyway to
minimize the load on my PC at home. So what setup would you recommend?
Wireless is strongly preferred due to some pretty tough logistics
constraints, but will it support this bandwidth? My receiver has it's own
DAC's, so straight CD output or at least output that my receiver could
handle the DA conversion would be ideal.

Well, if you want to do uncompressed audio, it's typically recommended to
use a wired-only Squeezebox connected to an 802.11g bridge device, and an
802.11g router/AP. It's not the most elegant of solutions, but it works very
well... I use this configuration at home for streaming uncompressed FLAC to
the stereo in my bedroom... Wired ethernet also works quite well for
streaming uncompressed...


I'm sorry for the length of the e-mail, but I look forward to your
response. I want to have this project complete by Christmas!

That should be plenty of time. Especially if you've already done all the
ripping...

----- Original Message -----
From: "Steve Baumgarten" <sbb (AT) panix (DOT) com>
To: "Slim Devices Discussion" <discuss (AT) lists (DOT) slimdevices.com>
Sent: Thursday, December 30, 2004 10:00 AM
Subject: [slim] Bit Rates for MP3?


> > I am a little surprised by this comment Jules. Does this mean that my
MP3s
> > are degraded in sound quality if they are recompressed at 320 CBR? Or am
I
> > misunderstanding what you mean by the wireless squeezebox recoding the
> > songs?
>
> MP3 streams are sent as is; all other formats are first decoded to WAV
> and then (optionally) converted to 320kbps MP3 streams. The default
> behavior is to do the conversion on wireless connections but not on
> wired connections; however, you can change the default behavior via a
> server setting.
>
> (This is how I have my Squeezebox set up -- it is on a wireless
> connection, but it plays uncompressed WAV streams from the server for
> all non-MP3 files. This allows me to listen to my FLAC files with full
> fidelity.)
>
> SBB
>
>
>
>
>
> Visit our website at http://www.ubs.com
>
> This message contains confidential information and is intended only
> for the individual named. If you are not the named addressee you
> should not disseminate, distribute or copy this e-mail. Please
> notify the sender immediately by e-mail if you have received this
> e-mail by mistake and delete this e-mail from your system.
>
> E-mail transmission cannot be guaranteed to be secure or error-free
> as information could be intercepted, corrupted, lost, destroyed,
> arrive late or incomplete, or contain viruses. The sender therefore
> does not accept liability for any errors or omissions in the contents
> of this message which arise as a result of e-mail transmission. If
> verification is required please request a hard-copy version. This
> message is provided for informational purposes and should not be
> construed as a solicitation or offer to buy or sell any securities or
> related financial instruments.
>
>

Mike Hartley
2004-12-30, 10:14
thnmnt,
Please see the e-mail from SLIM that I sent in response to Bitrate for MP3.
I meant to send it in response to your question, but I guess it fits both.

Regards,

Mike
----- Original Message -----
From: "thnmnt" <thnmnt (AT) hotmail (DOT) com>
To: "Slim Devices Discussion" <discuss (AT) lists (DOT) slimdevices.com>
Sent: Thursday, December 30, 2004 10:27 AM
Subject: [slim] Native format question


> i'm a little confused about native formats supported by sb/slim and what
> they mean exactly - is this a factor of the sb hardware? or the server
> software? for instance, i understand that AAC/MP4 gets converted on the
fly
> and sends uncompressed files to the sb - which can be problematic with a
> wireless setup. is it possible that this and other formats "become native"
> in the future? or is it just the nature of the beast that it was designed
> for mp3 and everything gets converted to it. sorry if this doesn't make
> sense - but i can't really wrap my head around it. i'm not asking for this
> so much as just..you know, wondering.
>

thnmnt
2004-12-30, 11:15
hmm, i knew this part - i guess my question more specifically was - are
native formats able to be added, and are they a factor of the hardware's
firmware, the server's software - or both?

----- Original Message -----
From: "Mike Hartley" <mhartley (AT) comsolusa (DOT) com>
To: "Slim Devices Discussion" <discuss (AT) lists (DOT) slimdevices.com>
Sent: Thursday, December 30, 2004 12:14 PM
Subject: [slim] Native format question


> thnmnt,
> Please see the e-mail from SLIM that I sent in response to Bitrate for
MP3.
> I meant to send it in response to your question, but I guess it fits both.
>
> Regards,
>
> Mike
> ----- Original Message -----
> From: "thnmnt" <thnmnt (AT) hotmail (DOT) com>
> To: "Slim Devices Discussion" <discuss (AT) lists (DOT) slimdevices.com>
> Sent: Thursday, December 30, 2004 10:27 AM
> Subject: [slim] Native format question
>
>
> > i'm a little confused about native formats supported by sb/slim and what
> > they mean exactly - is this a factor of the sb hardware? or the server
> > software? for instance, i understand that AAC/MP4 gets converted on the
> fly
> > and sends uncompressed files to the sb - which can be problematic with a
> > wireless setup. is it possible that this and other formats "become
native"
> > in the future? or is it just the nature of the beast that it was
designed
> > for mp3 and everything gets converted to it. sorry if this doesn't make
> > sense - but i can't really wrap my head around it. i'm not asking for
this
> > so much as just..you know, wondering.
> >

kdf
2004-12-30, 12:33
MP3 native is handled by specific hardware, PCM is handled by CPU. Other
formats would also have to be handled by cpu and would then depend on the
horsepower of the cpu (which isn't all that much) and the memory requirements
for decoding. Any native formats would be entirely firmware related at this
point provided the hardware can handle it. The only software changes would be
to convert.conf
-kdf
Quoting thnmnt <thnmnt (AT) hotmail (DOT) com>:

> hmm, i knew this part - i guess my question more specifically was - are
> native formats able to be added, and are they a factor of the hardware's
> firmware, the server's software - or both?
>
> ----- Original Message -----
> From: "Mike Hartley" <mhartley (AT) comsolusa (DOT) com>
> To: "Slim Devices Discussion" <discuss (AT) lists (DOT) slimdevices.com>
> Sent: Thursday, December 30, 2004 12:14 PM
> Subject: [slim] Native format question
>
>
> > thnmnt,
> > Please see the e-mail from SLIM that I sent in response to Bitrate for
> MP3.
> > I meant to send it in response to your question, but I guess it fits both.
> >
> > Regards,
> >
> > Mike
> > ----- Original Message -----
> > From: "thnmnt" <thnmnt (AT) hotmail (DOT) com>
> > To: "Slim Devices Discussion" <discuss (AT) lists (DOT) slimdevices.com>
> > Sent: Thursday, December 30, 2004 10:27 AM
> > Subject: [slim] Native format question
> >
> >
> > > i'm a little confused about native formats supported by sb/slim and what
> > > they mean exactly - is this a factor of the sb hardware? or the server
> > > software? for instance, i understand that AAC/MP4 gets converted on the
> > fly
> > > and sends uncompressed files to the sb - which can be problematic with a
> > > wireless setup. is it possible that this and other formats "become
> native"
> > > in the future? or is it just the nature of the beast that it was
> designed
> > > for mp3 and everything gets converted to it. sorry if this doesn't make
> > > sense - but i can't really wrap my head around it. i'm not asking for
> this
> > > so much as just..you know, wondering.
> > >