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david68
2007-06-28, 01:07
Hi,

Out of interest I downloaded a couple of tracks from Linn Records last night - both FLAC files at their 24bit Studio Master quality. As regards bitrates, one reports as being 1761kbps and the other 2701kbps.

With my SB3 connected wirelessly (router about 6 metres away in the next room with signal strength ranging from 70 to 80%) the lower bitrate track plays fine, but the higher bitrate track suffers from some breakup/stuttering (technical term?).

I then found a 10m ethernet cable and tried wired mode. With it connected this way both tracks play fine, so clearly my wireless connection is just not up to the job. However, trying the SlimServer 'Network Test' at 3000kbps does report around a 99% average.

Can anyone tell me if this is what I should be expecting with wireless, or is my setup performing below the norm? If I thought I could get better performance wirelessly I'd be more than willing to buy a new/better router. I'm currently using a Speedtouch 716WL(v5).

Cheers
David

tot
2007-06-28, 03:24
The faster bitrate is really pushing to the limits of what 802.11g can do.

I tested once 24bit/96kHz flac and had the same problem over wireless (router has even directional high-gain antenna). Since SB3 can not really do 96kHz anyway why not downsample them to 48kHz, they work just fine over wireless.

Teemu

Manelus
2007-06-28, 03:38
I play lots of 24bit/96kHz flacs (I use Transporter) with no problems at all.
My router is a 4 years old 3COM office connect.
Maybe Trasporter v. SB3 ?

tot
2007-06-28, 03:57
I play lots of 24bit/96kHz flacs (I use Transporter) with no problems at all.
My router is a 4 years old 3COM office connect.
Maybe Trasporter v. SB3 ?

Must be SB3 then, I wrote bollocks (10x error in speed what 802.11g can do).

Teemu

Ron F.
2007-06-28, 07:19
David68,

The SB3 does not have the processing power to decompress a 96KHz FLAC file. If you transcode to FLAC compression level 0 in Slimserver, the stuttering should stop.

Without stuttering, you will still have a problem - the SB3 does not filter the stream, nor down-sample from 96KHz to 48Khz, it merely decimates.

I recommend you down-sample any 96KHz FLAC files you download from Linn Records to 48KHz using Audacity or dBpowerAMP before streaming them to the SB3.

-Ron

david68
2007-06-28, 13:19
Thanks for the responses. I'm on a steep learning curve at present so much appreciated.

I looked at the properties of both downloaded Linn files and (in-line with what you said) the one that plays fine has a Sample Rate of 44.1khz. The problem one was 96khz.

Is it better to downsample to 48khz then, rather than 44.1khz?

Thanks
David

Ron F.
2007-06-28, 16:17
Theoretically, there should be little difference between 48KHz and 44.1 Khz. Nevertheless, I have down-sampled some 96KHz material, and it sounds awfully good. Maybe it is just wishful thinking on my part.

I have made comparisons of the same material: 44.1KHz-16bit versus 48KHz-24bit that originated as 96KHz-24bit. Given 30 seconds - I cannot tell the difference. However, if I listen for an hour, the lower resolution material becomes more tiresome to listen to.

Your mileage will definitely vary, but if you are going to down-sample from 96KHz, then down-sampling to 48KHz is better.

-Ron