help - sound dropouts - streaming 192 OR 96 to nd5

Posted by: ash on 10 July 2012

gentlemen

 

i understand this has been raised more than once, but i cannot seem to find a satisfactory solution suggested in the posts, so...

 

the setup is apple airport extreme into netgear xe104, another xe104 into nd5. streaming from mybook nas into xe104 or from macbookpro wirelessly

 

the issue: 16-44 stream fine, but streaming either 96 or 192 quickly lead to "under buffering" and the sound dropouts

 

would appreciate any comments or suggestions 

 

with kind regards

 

 

   

Posted on: 11 July 2012 by Party Pete

Thanks Phil. As I'm so close with wireless I am thinking of a better specced router perhaps with separate extender to convert the wifi into Ethernet for the Unitiqute which I understand relies on wireless 802.11b rather the later wireless n? Of course, I realise there are no guarantees. 

Posted on: 11 July 2012 by Phil Harris
Originally Posted by Party Pete:

Thanks Phil. As I'm so close with wireless I am thinking of a better specced router perhaps with separate extender to convert the wifi into Ethernet for the Unitiqute which I understand relies on wireless 802.11b rather the later wireless n? Of course, I realise there are no guarantees. 

 

For WiFi connections the highest resolution that we support is 24bit/48kHz ... any higher *MAY* play but we won't guarantee it.

 

Cheers

 

Phil

Posted on: 11 July 2012 by Frank Abela

802.11b? I think you can forget it, per wikipedia:

 

"802.11b has a maximum raw data rate of 11 Mbit/s and uses the same CSMA/CA media access method defined in the original standard. Due to the CSMA/CA protocol overhead, in practice the maximum 802.11b throughput that an application can achieve is about 5.9 Mbit/s using TCP and 7.1 Mbit/s using UDP."

 

For high resolution audio, you need a minimum of 8Mbps...and therefore a minimum of Wireless g (Wireless n only extends range, not throughput so if you're close g or n make no difference - at least that's my understanding).

 

Regards,
Frank.
All opinions are my own and do not reflect the opinion of any organisations I work for, except where this is stated explicitly.

Posted on: 11 July 2012 by Party Pete

I would agree but a Naim support person advised me that the Unitiqute only uses b. Can anyone confirm what version of wireless the qute supports? 

Posted on: 11 July 2012 by Simon-in-Suffolk

Frank, 802.11n is very different from 802.11g. Not only does it use extended range features using multiple antennas as you say, but also supports upto 4 concurrent channels at double bandwidth (40MHz) and can provide upto 600 Mbps throughput before overheads, whereas 802.11g supports only up to 54Mbps before overheads.

If the 802.11n senses legacy wifi channels in the environment it has to downgrade to standard width  bandwidth channels (20Mhz) and max throughput for 4 concurrent channels drops to 300Mbps (2 channels 150Mbps and one channel approx 75Mbps). The number of concurrent channels supported is down to the radios being used.(transceivers at each end), 

 

But remember with wifi, on most standard configs data is only transmitted in one direction at once, and also collision detection and retry algorithms are used (ie Mutiple devices try and transmit on the sama wifi network, or wifi channel at once), therefore effective throughput will always be a lot less than a conentional wired duplex network at the same headline data throughput speed; that is 100mbps on a wired LAN is significantly more effective than 100Mbps on a wifi network.

 

Simon

 

Posted on: 12 July 2012 by ash
Tried out Phil's suggestion. Plugged Mybook World nas into apple airport extreme, airport extreme into nd5. Airport extreme was creating a 5hz wifi network. Results: n
Posted on: 12 July 2012 by ash
... (sorry) the results: not only did the nas-stored 192's played flawlessly, - but MacBook wifi streamed 192's DID TOO. Buffer fluctuated in the latter case, but never went below 50%. Thus eliminating from the chain the second wifi segment (originally nd5 was connecting to the network wirelessly) apparently bore fruit. Phil - many thanks for the insight
Posted on: 12 July 2012 by Phil Harris
Originally Posted by Party Pete:

I would agree but a Naim support person advised me that the Unitiqute only uses b. Can anyone confirm what version of wireless the qute supports? 

 

It's 802.11g or n at 2.4GHz... (According to my specs on the current 24/192 hardware)

 

Cheers

 

Phil

Posted on: 12 July 2012 by Party Pete

Thanks. That makes a lot more sense to me as b is pretty old hat.