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pedalvet
2006-02-17, 15:23
I'm wondering how much bandwidth is needed to stream flac? I want to use a Belkin Powerline network- which has 14Mbps. Is that enough? My computer is on the 3rd floor in the front of the house, and my stereo on the ground floor in the back. I've had great trouble with wireless over that distance in the past.

Thanks!

funkstar
2006-02-17, 15:51
Your main problem won't be the streaming of FLAC, it will be maintianing a connection to the wireless network. The SB can be a little tempremental with some wireless networks at the moment (although there is a lot of work right now in updating the firmware to improve the situation).

Have a look at the WiKi, there is a page with compatability information on various routers (http://wiki.slimdevices.com/index.cgi?RouterStatus). The two versioins of the Belkin Pre-N are listed with special notes too. Looks like you might be in luck as it says the v1 virmware has "outstanding range", but as always with wirless, Your Milage May Vary

good luck :)

ceejay
2006-02-17, 16:08
Actully, funkstar, I think OP is trying to avoid wireless by using his power lines ...

You might want to check the actual bandwidth you are getting (its unlikely to be close to nominal) but even if you are getting only 7Mbit/s you should be fine - a typical FLAC stream is 1MBit/s or less.

Ceejay.

pablolie
2006-02-17, 16:15
I limit my wireless devices to 2 Mbps, it is an option on the Linksys router I use. The SB works just fine with 2 Mbps, and I am not surre why anyone would expect the contrary - an uncompressed HiFi audio stream is nowhere near that.

Incidentally, coded at 256k MP3 I hear no difference whatsoever on the vast majority of albums, and even on those I think to detect "something" I am hard-pressed to hear it.

cjhabs
2006-02-17, 20:03
From my limited experience, my FLACs run about 8 megabytes per minute. My calculation is:
8 megabytes per minute = 80 megabits per minute = 1.3 megabits per second.

Michaelwagner
2006-02-17, 22:54
I'm wondering how much bandwidth is needed to stream flac? I want to use a Belkin Powerline network- which has 14Mbps. Is that enough? My computer is on the 3rd floor in the front of the house, and my stereo on the ground floor in the back. I've had great trouble with wireless over that distance in the past.

Thanks!
I bought a powerline system to play with exactly this scenario. I'm still waiting for them to be delivered. I'll update the list with my results when I know more.

Pale Blue Ego
2006-02-18, 00:28
I'm using powerline adapters for 2 Squeezeboxes (a 3rd SB is wired using cat-5). They work extremely well. I'm getting the full 14 Mbps on one of the connections; the other is a little slower, but still delivers 12 Mbps. For FLAC you only need about 1 Mbps.

The only problem I've had was after a power failure. I lost the powerline connections and had to unplug/replug the adapter nearest the router. Takes 2 seconds to fix.

funkstar
2006-02-18, 07:27
My appologies, i missed that it was powerline networking the OP was using. I really should read things more closely :)

pedalvet
2006-02-18, 07:42
You might want to check the actual bandwidth you are getting Ceejay.

Ceejay-
Great suggestion, don't know why I didn't think of it. I seem to get 1.2 to 2.5 Mbps on most trials, however once in a while it drops down to 500kbps. I'm afraid this might cause dropouts, but I think I'll give it a try.

Thanks to all for your feedback! This forum is a tremendous resource, and frankly a big selling point for SB.

Dave

Michaelwagner
2006-02-18, 07:47
I seem to get 1.2 to 2.5 Mbps on most trials, however once in a while it drops down to 500kbps. I'm afraid this might cause dropouts, but I think I'll give it a try.

Which SB are you going to be using?

The SB2s and 3s have big buffers and can make use of a variable bandwidth connection by smoothing over the bumps with buffering.

The older ones have a harder time with this sort of connection.


This forum is a tremendous resource, and frankly a big selling point for SB.

Sean? How are those commission cheques coming? :-)

(we are not in the employ of Slim Devices ...we just like their products so much we help out "pour le sport")

pedalvet
2006-02-18, 10:04
[QUOTE=Michaelwagner]The SB2s and 3s have big buffers


Well that's awesome. I'm going to get an SB3. In fact I might order it right now!

pablolie
2006-02-18, 11:55
> The SB2s and 3s have big buffers and can make use of a
> variable bandwidth connection by smoothing over the bumps with
> buffering.

I was curious about buffer sizes, according to the Wiki it's about 25MB, which lasts about 10secs at uncompressed 1.4Mbps speeds. Given the fact wireless networks operate at a significantly faster speed, even lousy connections should be more than enough to support audio, though.

Mine works fine even though I limit my wireless devices (for now) to 2Mbps, even at occasional 50% signal quality. When spring comes and I set up a SQB in the garden, it may get interesting, I'll report.

And if the wireless network is really unreliable, people should get a booster antenna and see whether that helps in their environment. But don't forget to secure your network, extended range means extended vulnerability!

Michaelwagner
2006-02-18, 19:10
On my SB1, I can shut the server off (or cut the ethernet connection - same thing) and the player plays for 5 to 10 seconds (mp3, 320Kbs CBR).

On my SB3, it's over a minute.

pablolie
2006-02-18, 19:47
> .. (mp3, 320Kbs CBR).
> On my SB3, it's over a minute.

Oh, I totally agree. All I am saying is that large buffers are relative. I store my MP3s at 256kbps CBR, and if I disconnect the server the SB3 seems able to finish whatever song it's playing, no problem. Which is not surprising, given the fact that a typical song would be from 6-10MB, and thus a 25MB buffer is sufficient to hold 2 or 3 songs.

Of course, things are a bit different for those who claim to hear a difference and use 1.4Mbps uncompressed transmission, since then within 10s the buffer is depleted.

One thing I am curious about and have never found much information on is how and when the SB3 requests additional blocks/songs. By looking at bandwidth use out of the computer, with MP3s the SB3 seems to download an entire song in a short burst as the song starts, and then does not need bandwidth until the next song is up - it's always bursts as the song starts. I am sure it's a bit more complex than that, since working uncompressed downloading a whole song is not an option.

Michaelwagner
2006-02-18, 20:40
a typical song would be from 6-10MB, and thus a 25MB buffer is sufficient to hold 2 or 3 songs.
Careful. That's a 25 mega-bit buffer, not mega-byte.


One thing I am curious about and have never found much information on is how and when the SB3 requests additional blocks/songs.
The details are complicated, but the SB has a way of telling the server how full it's buffer is and when it would like more song data.

The SB3 lets the buffer drain almost completely at the end of a song, and then makes an effort to fill the buffer at the beginning of the next song, so you are likely correct that it pigs out at the beginning of a song.

However, I expect that, for most "normal" sized songs, you are incorrect that the whole song fits into the buffer. More likely, that's the obvious spike, and the rest kind of dribbles and is harder to see.

I just played a song with a performance monitor running. On an SB3, essentially all flow of data to the SB stops about 80 seconds before the end of the song. For the first 28 seconds of the next song, the data transfer is relatively high, then it settles down, and again stops about 80 seconds from the end of the song.

Again, all measurements at 320Kbps CBR.

pablolie
2006-02-18, 22:18
Thanks a lot for the very informative message, appreciate it. Also, thanks for correcting me on the memory. Upon re-reading the data I discovered that, indeed, "25Mb (approx. 200 seconds at 128Kbps) compresessed", which is like, whoa, they really keep the little box dumb. Memory is so cheap. However, the box sounds great. It amazes me, in fact. Cheapest gear connected to my system, I own cables that cost twice as much, and yet I rely on the little box more and more as I rip more and more of my CDs...

Mark Lanctot
2006-02-19, 13:41
Upon re-reading the data I discovered that, indeed, "25Mb (approx. 200 seconds at 128Kbps) compresessed", which is like, whoa, they really keep the little box dumb. Memory is so cheap.

Well yes, but this is SDRAM soldered directly onto the board. No DIMM sockets here, see second-last photo:

http://www.slimdevices.com/photos/inside_squeezebox2/

(Note the SB3 has nearly identical hardware in a different form factor).

So costs are comparatively much higher.

Michaelwagner
2006-02-19, 13:52
Hey Mark:

Do you know anything about the "secondary antenna" marked in one of those photos?

I don't have an SB2 (and all my '3's are wired) but does that mean an SB2 can run without the stub antenna? And hope to succeed?

pablolie
2006-02-19, 14:03
[QUOTE=Mark Lanctot]Well yes, but this is SDRAM soldered directly onto the board.

Indeed, much faster memory, much higher cost. One wonders why one would need very fast memory for music reproduction, however probably that's where the secret sauce is, and therein may lie the great secret of the little box' great sound... ;-)

Thanks for the educational messages in this thread, gentlemen.

Michaelwagner
2006-02-19, 14:28
It's not a separate chip for buffer memory. The specs are documenting how the memory pool is divided up, but I suspect there's just the one chip for all uses, including the custom programmed software DSP. Perhaps *it* needs the higher memory speed.

Michaelwagner
2006-02-19, 14:29
Thanks for the educational messages in this thread, gentlemen.
We strive to be entertaining.

...

Hopefully we're also correct (at least most of the time :-) )

Mark Lanctot
2006-02-19, 18:32
Hey Mark:

Do you know anything about the "secondary antenna" marked in one of those photos?

I don't have an SB2 (and all my '3's are wired) but does that mean an SB2 can run without the stub antenna? And hope to succeed?

You know, that's an interesting thought. I'll try running my SB2 that way tonight and see what happens.

I don't mind the antenna though, but you have made me curious.

EDIT: BWA HA HA! Although my SB2 is very, very close to the router (about 15 feet away in the next room), it works perfectly. Strength with the rubber ducky antenna attached was 93%. Strength with the antenna removed had only dropped to 80%! Reconnection to the server was instantaneous.

I should post that info in the "wireless signal seems a bit delicate" thread. ;-)

Michaelwagner
2006-02-19, 18:41
I'll try running my SB2 that way tonight and see what happens.
Maybe it'll turn your SB2 into an SB3 and you'll have all those weird signal strength problems the '3's have :-)

By the way, I bought some power line ethernet adaptors and am waiting for them to be delivered ... see if I like that more than wireless.

Mark Lanctot
2006-02-19, 20:42
--- Michaelwagner
<Michaelwagner.23i84b1140399990 (AT) no-mx (DOT) forums.slimdevices.com>
wrote:

> By the way, I bought some power line ethernet
> adaptors and am waiting
> for them to be delivered ... see if I like that more
> than wireless.

At the risk of getting OT, where did you end up
getting them? I'm having a hard time finding this
equipment here. My usual supplier is NCIX - they have
the old 14 Mbps stuff at an outrageous price buried in
an obscure page on their site that takes 10 minutes to
get to.

Michaelwagner
2006-02-19, 21:45
eBay. :-)
fill
for
forum
software

Michaelwagner
2006-02-19, 21:51
At the risk of getting OT
We could pick up in this thread:
http://forums.slimdevices.com/showthread.php?t=16579&highlight=powerline+ethernet