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obstreperousness
2006-07-19, 18:34
I don't have a Squeezebox yet, but I've ordered one. I'm excited, and I think I'm right to be! Meanwhile, here are two questions I hope someone can answer:

Is the Squeezebox capable of playing better-than 16-bit/44.1kHz PCM audio files without dithering/downsampling? What is SlimServer+Squeezebox going to do when I send it 24-bit/96kHz WAVs?

Can I shunt the audio output of my computer to the Squeezebox? I want to hear whatever is flowing through the Windows system mixer come out of the SB3. Possible? (I gather from looking at the forums I could run a streaming media server to feed SlimServer's radio function. I'm guessing there's noticeable delay using this method.)

Thanks!
Ryan

pfarrell
2006-07-19, 18:47
obstreperousness wrote:
> I don't have a Squeezebox yet, but I've ordered one. I'm excited, and I
> think I'm right to be!

You bet, I love mine, all three of them

> Is the Squeezebox capable of playing better-than 16-bit/44.1kHz PCM
> audio files without dithering/downsampling? What is
> SlimServer+Squeezebox going to do when I send it 24-bit/96kHz WAVs?

I'll have to let someone else answer this part.
I think it will do 24/44.

> Can I shunt the audio output of my computer to the Squeezebox? I want
> to hear whatever is flowing through the Windows system mixer come out
> of the SB3. Possible?

What are you really trying to do?
The SqueezeBox only plays music that comes over its Ethernet port.
Most soundcards (or motherboard equivalents) don't output to the
Ethernet. So the obvious (or trivial) answer is no. Of course,
its a computer and you can probably do something to capture the
output so some sort of virtual driver or loopback on the sound card
and then send that out the Ethernet.

There are plug-ins that let you do things like apply EQ, adjust
gain, etc. and you could probably find some way to apply generic
effects (reverb, chorus, flange, compression) from an audio
toolkit like Calkwalk Sonar, but I like my music straight up.

--
Pat
http://www.pfarrell.com/music/slimserver/slimsoftware.html

Mark Lanctot
2006-07-19, 18:57
Is the Squeezebox capable of playing better-than 16-bit/44.1kHz PCM audio files without dithering/downsampling? What is SlimServer+Squeezebox going to do when I send it 24-bit/96kHz WAVs?

It can play 24/48 but not 24/96. Apparently it plays 96 kHz material at half-speed.

obstreperousness
2006-07-19, 19:03
obstreperousness wrote:
> Can I shunt the audio output of my computer to the Squeezebox? I want
> to hear whatever is flowing through the Windows system mixer come out
> of the SB3. Possible?

What are you really trying to do?
The SqueezeBox only plays music that comes over its Ethernet port.
Most soundcards (or motherboard equivalents) don't output to the
Ethernet. So the obvious (or trivial) answer is no.

Well, say I'm watching a DVD on the computer. I want the sound to come out of the SB3 rather than (or in addition to) the computer's sound card. Benefits: fairly high-quality DAC and output stage in SB3 - better than most sound cards, and wireless transmission to the stereo, which wouldn't have to be physically connected to the computer at all.
I understand the latency introduced by the SlimServer software and the network transit might add unacceptable delay.

Think of it this way: I want to use the SB3 as my sound card. The question is, is it possible?

nickrout
2006-07-19, 19:12
As I understand the SB it plays what is streamed to it over the network. If you can stream the sound from your DVD to the address occupied by the SB then it may just be possible.

VLC may be able to do this, although I am not sure whether it can stream the video and audio segments to different places.


On Wed, 19 Jul 2006 19:03:39 -0700
obstreperousness wrote:

>
> pfarrell Wrote:
> > obstreperousness wrote:
> > > Can I shunt the audio output of my computer to the Squeezebox? I
> > want
> > > to hear whatever is flowing through the Windows system mixer come
> > out
> > > of the SB3. Possible?
> >
> > What are you really trying to do?
> > The SqueezeBox only plays music that comes over its Ethernet port.
> > Most soundcards (or motherboard equivalents) don't output to the
> > Ethernet. So the obvious (or trivial) answer is no.
>
> Well, say I'm watching a DVD on the computer. I want the sound to come
> out of the SB3 rather than (or in addition to) the computer's sound
> card. Benefits: fairly high-quality DAC and output stage in SB3 -
> better than most sound cards, and wireless transmission to the stereo,
> which wouldn't have to be physically connected to the computer at all.
> I understand the latency introduced by the SlimServer software and the
> network transit might add unacceptable delay.
>
> Think of it this way: I want to use the SB3 as my sound card. The
> question is, is it possible?
>
>
> --
> obstreperousness
> ------------------------------------------------------------------------
> obstreperousness's Profile: http://forums.slimdevices.com/member.php?userid=6422
> View this thread: http://forums.slimdevices.com/showthread.php?t=25654
>
>

nickrout
2006-07-19, 19:33
On Thu, 20 Jul 2006 14:12:56 +1200
Nick Rout wrote:

> As I understand the SB it plays what is streamed to it over the network. If you can stream the sound from your DVD to the address occupied by the SB then it may just be possible.
>
> VLC may be able to do this, although I am not sure whether it can stream the video and audio segments to different places.


Thinking more about it, i don't know what streams the SB will accept, I
don't know what gets converted in the server and what gets converted in
the SB itself.

But DVD sound is not in mp3 format, which may mean that there has to be
a conversion to an appropriate format before streaming, which will give
a further delay, on top of that inherent in a network setup. Also you
will want some caching for those inevitable network glitches and that
gves more delay.

from http://en.wikipedia.org/wiki/DVD

"The audio data on a DVD movie can be PCM, DTS, MP2, or Dolby Digital (AC-3) format. In countries using the NTSC standard any movie should contain a sound track in (at least) either PCM or Dolby AC-3 format; any NTSC player must support these two formats, the others being optional. This ensures any standard compatible disc can be played on any standard compatible player. The vast majority of commercial NTSC releases today employ AC-3 audio. The official allowed formats for the audio tracks on a DVD Video are:

* PCM: 48 kHz or 96 kHz sampling rate, 16 bit or 24 bit L-PCM, 2 to 6 channels, up to 6144 kbit/s
* AC3: 48 kHz sampling rate, 2 to 5 (6) channels, up to 448 kbit/s
* DTS: 48 kHz sampling rate, 2 to 6 channels, Half Rate (768 kbit/s) or Full Rate (1536 kbit/s)
* MPEG-1 Layer 2: Europe only, 48 kHz

* Up to 8 audio tracks containing Dolby Digital, DTS, PCM (uncompressed audio) or MPEG1 Layer2. (One audio track must have MPEG-1, Dolby Digital or PCM Audio.)

Initially, in countries using the PAL standard (e.g. most of Europe) the sound of DVD was supposed to be standardized on PCM and MP2, but apparently against the wishes of Philips, under public pressure on December 5, 1997, the DVD Forum accepted the addition of Dolby AC-3 to the optional formats on discs and mandatory formats in players. The vast majority of commercial PAL releases now employ AC-3 audio."
--
Nick Rout <nick (AT) rout (DOT) co.nz>

obstreperousness
2006-07-19, 20:06
On Thu, 20 Jul 2006 14:12:56 +1200
Nick Rout wrote:

But DVD sound is not in mp3 format, which may mean that there has to be
a conversion to an appropriate format before streaming, which will give
a further delay, on top of that inherent in a network setup. Also you
will want some caching for those inevitable network glitches and that
gves more delay.
DVD playback software sends a PCM stream to the operating system sound driver, regardless of the audio format contained on the disc - the DVD playback software itself is responsible for decoding the DTS/AC3/MLP/&c..
DVD playback was simply an example I chose. For my purposes, the source could be anything - any audio-producing application. They all send PCM data to the sound card driver. Sound Forge, QuickTime, PowerDVD, Windows Media Player, foobar2000, you-name-it.

Think of it this way: I want to use the SB3 as my sound card.

Thanks for the research, Nick!

Mark Lanctot
2006-07-19, 20:13
Think of it this way: I want to use the SB3 as my sound card.

Not possible at present. This is why a streaming server is usually recommended.

funkstar
2006-07-19, 21:13
Think of it this way: I want to use the SB3 as my sound card.
This comes up a lot. Search for IceCast or ShoutCast in the forums for some similar threads and discussions.

Marc Sherman
2006-07-20, 05:33
obstreperousness wrote:
>
> Think of it this way: I want to use the SB3 as my sound card. The
> question is, is it possible?

As others have said, you'll have to use a streaming server, which will
introduce delays; sounds will go from the app the makes them, to the
windows sound driver, to the streaming server, to the slimserver, over
the network to the squeezebox.

In the end, I highly doubt you'll be happy with this setup. At a
fundamental level, you're putting a square peg in a round hole. The
squeezebox was designed to be a remote music player, away from your
computer, not a component of your computer in the same room.

- Marc

bishopdonmiguel
2006-07-20, 09:46
obstreperousness wrote:
> Think of it this way: I want to use the SB3 as my sound card.

Before owning a SB, I bought a Stereo-Link 1200 to output all the PC sound to my amp. Worked VERY well but I no longer use it. If your sound system is within RCA cable range, I've got a used Stereo-Link that can be had for a reasonable price. PM me if interested.

obstreperousness
2006-07-20, 09:59
Before owning a SB, I bought a Stereo-Link 1200 to output all the PC sound to my amp. Worked VERY well but I no longer use it. If your sound system is within RCA cable range, I've got a used Stereo-Link that can be had for a reasonable price. PM me if interested.

Interesting, thanks. I have pretty good quality M-Audio 24/96 sound card that I'm pretty happy with. I'm just exploring the options the Squeezebox provides.

nickrout
2006-07-20, 13:57
On Thu, 20 Jul 2006 09:46:06 -0700
bishopdonmiguel wrote:

>
> obstreperousness wrote:
> > Think of it this way: I want to use the SB3 as my sound card.
>
> Before owning a SB, I bought a Stereo-Link 1200 to output all the PC
> sound to my amp. Worked VERY well but I no longer use it. If your
> sound system is within RCA cable range, I've got a used Stereo-Link
> that can be had for a reasonable price. PM me if interested.


Why is this superior to a line out from your sound card to your stereo?
Is it to do with the quality of the DAC in the Stereo-Link as opposed to
the DAC in the average sound card?



--
Nick Rout <nick (AT) rout (DOT) co.nz>

nickrout
2006-07-20, 14:09
On Wed, 19 Jul 2006 20:06:23 -0700
obstreperousness wrote:

>
> nickrout Wrote:
> > On Thu, 20 Jul 2006 14:12:56 +1200
> > Nick Rout wrote:
> >
> > But DVD sound is not in mp3 format, which may mean that there has to
> > be
> > a conversion to an appropriate format before streaming, which will
> > give
> > a further delay, on top of that inherent in a network setup. Also you
> > will want some caching for those inevitable network glitches and that
> > gves more delay.
> DVD playback software sends a PCM stream to the operating system sound
> driver, regardless of the audio format contained on the disc - the DVD
> playback software itself is responsible for decoding the
> DTS/AC3/MLP/&c..
> DVD playback was simply an example I chose. For my purposes, the source
> could be anything - any audio-producing application. They all send PCM
> data to the sound card driver. Sound Forge, QuickTime, PowerDVD,
> Windows Media Player, foobar2000, you-name-it.


Yes i appreciate that, I was suggesting that you stream the sound
separately to the video - sound to the sb via a stream and video to your
screen.


>
> Think of it this way: I want to use the SB3 as my sound card.

Can someone clarify for me - what formats are transmitted across the
wire to the streambox? Is there any conversion on the server, or does
the streambox do all conversion from the myriad formats it supports? I
had a feeling that everything was converted to mp3 on the server and
streamed to the SB as mp3, but I may be way wrong or out of date.

It would be possible to write a driver that takes the pcm output from
the average sound app and converts it to what the SB wants and then
streams it. NAS (Network Audio System) does a similar thing
http://radscan.com/nas.html . I sometimes use NAS to get sound around my
house over the LAN.

Unfortunately your choice of operating system may prevent you from doing
anything along those lines.

I think that any such system is going to have inherent network and
conversion delay problems. It'll make video unwatchable, but may be ok
for pure audio. However if you have pure audio, why not just use the SB
as it was intended?


>
> Thanks for the research, Nick!
>
>
> --
> obstreperousness
> ------------------------------------------------------------------------
> obstreperousness's Profile: http://forums.slimdevices.com/member.php?userid=6422
> View this thread: http://forums.slimdevices.com/showthread.php?t=25654
>
>

Mark Lanctot
2006-07-20, 14:48
Can someone clarify for me - what formats are transmitted across the
wire to the streambox? Is there any conversion on the server, or does
the streambox do all conversion from the myriad formats it supports? I
had a feeling that everything was converted to mp3 on the server and
streamed to the SB as mp3, but I may be way wrong or out of date.

It will send audio in any format it can decode natively:

- MP3
- WAV/PCM
- FLAC
- AIFF
- WMA
- Ogg (new)

Anything else will be transcoded to one of these formats in the server. No transcoding takes place in the player.



It would be possible to write a driver that takes the pcm output from
the average sound app and converts it to what the SB wants and then
streams it. NAS (Network Audio System) does a similar thing
http://radscan.com/nas.html . I sometimes use NAS to get sound around my
house over the LAN.

Yes indeed. This is an open-source project, so as they say, patches are welcome. It's fairly frequently requested and it would allow some neat features like instant playback of a CD right off the server's optical drive.

But the fact that we haven't seen anything yet must mean it's more difficult than it sounds. It would also be OS-specific, which is contrary to the SlimServer approach.

bishopdonmiguel
2006-07-20, 14:51
nickrout wrote:

> Why is this superior to a line out from your sound card to your stereo?
> Is it to do with the quality of the DAC in the Stereo-Link as opposed to
> the DAC in the average sound card?

I'm not enough of an audiophile to know how the Stereo-Link DAC compares to that of a normal soundcard, although we website claims it's high quality but I have no way of knowing. At the time, I had a long run from the computer to the stereo (in another room perhaps 30 feet), and the signal from the PC audio-out had significant distortion and hum. The Stereo-Link claimed to handle runs up to 80' and it seemed worth a try. It did the job very well and I also used it as a handy driver for headphones (just click the on button and the PC sound goes out while the headphones are activated). Sound was very good, at least for my ears, and it eliminated all the issues I had at the time. Then I ran across the SliMP3 and haven't used it much for music, although it still comes in handy for listening to some internet radio that SlimServer can't deal with.

nickrout
2006-07-20, 15:18
On Thu, 20 Jul 2006 14:48:39 -0700
Mark Lanctot wrote:

> nickrout Wrote:
> > Can someone clarify for me - what formats are transmitted across the
> > wire to the streambox? Is there any conversion on the server, or does
> > the streambox do all conversion from the myriad formats it supports? I
> > had a feeling that everything was converted to mp3 on the server and
> > streamed to the SB as mp3, but I may be way wrong or out of date.
>
> It will send audio in any format it can decode natively:
>
> - MP3
> - WAV/PCM
> - FLAC
> - AIFF
> - WMA
> - Ogg (new)
>
> Anything else will be transcoded to one of these formats in the server.
> No transcoding takes place in the player.

Thank you for your helpful reply. So the SB will accept wav/pcm over the
wire? Apart from the fact that this will take up an order of magnitude
more bandwidth than, say, mp3 or ogg, that could be useful for the
approach that obstreperousness wanted to take.

In linux, alsa has hooks to send its output to arbirtrary
"destinations". Whether there is a "destination" to send the output as a
stream over a network, I do not know.

However the network delays will still get you. I don't fancy clicking a
button on my desktop and having the annoying system sound emerge from my
stereo 5 seconds later!


--
Nick Rout <nick (AT) rout (DOT) co.nz>

Mark Lanctot
2006-07-21, 05:34
Thank you for your helpful reply. So the SB will accept wav/pcm over the
wire? Apart from the fact that this will take up an order of magnitude
more bandwidth than, say, mp3 or ogg, that could be useful for the
approach that obstreperousness wanted to take.


Yes. Note a few things:

1. When you say "over the wire" keep in mind this is not at all like over an audio cable. It's a stream buried in Ethernet traffic and is in packet format. It's not even digital audio like over coaxial or optical cable.

2. You're correct in that WAV takes up an order of magnitude more bandwidth than MP3, which is why so many people with Squeezeboxes use FLAC. It's the same quality but takes up 40-60% less bandwidth through lossless compression.

obstreperousness
2006-07-21, 09:01
Yes. Note a few things:

1. When you say "over the wire" keep in mind this is not at all like over an audio cable. It's a stream buried in Ethernet traffic and is in packet format. It's not even digital audio like over coaxial or optical cable.

2. You're correct in that WAV takes up an order of magnitude more bandwidth than MP3, which is why so many people with Squeezeboxes use FLAC. It's the same quality but takes up 40-60% less bandwidth through lossless compression.

Does that mean, then, I can fire an audio stream at the correct TCP port on the SB and expect it to turn it into sound, bypassing SlimServer and all its advanced features? Would you have to tell the SB anything else, like what format to expect? There's got to be more to it than that...
I don't actually have the SB yet, so these matters are purely ethereal. Just want to know what's possible.

Mark Lanctot
2006-07-21, 10:19
Does that mean, then, I can fire an audio stream at the correct TCP port on the SB and expect it to turn it into sound, bypassing SlimServer and all its advanced features? Would you have to tell the SB anything else, like what format to expect? There's got to be more to it than that...

No, I should have qualified my response.

The stream is sent using the SlimProto TCP Protocol. See here:

http://wiki.slimdevices.com/index.cgi?SlimProtoTCPProtocol

SlimServer generates the SlimProto packets and the SB has an interpreter to decode them. If you had a program that could generate SlimProto packets, then you could replace SlimServer. I'm currently unaware of a program that replaces SlimServer entirely. The alternate servers here still use the SlimServer CLI to generate packets: http://wiki.slimdevices.com/index.cgi?PluginRemoteControls

There's only one SlimProto player listed here:

http://wiki.slimdevices.com/index.cgi?PluginPlayers

and that's SoftSqueeze, although there's a simple command-line version called squeezeslave available at the SoftSqueeze SourceForge site in the Files section. The other players listed in the wiki are for the older SLIMP3 Client protocol.

BTW you can try out both SlimServer and SoftSqueeze right now as they are both free. In fact, it's a good idea to install SlimServer before you get a Squeezebox so you can get a feel for it.