Re: [LAD] 802.11n sound card

From: Arnold Krille <arnold@email-addr-hidden>
Date: Wed Dec 23 2009 - 11:08:51 EET

On Wednesday 23 December 2009 09:12:24 Patrick Shirkey wrote:
> On 12/23/2009 09:40 AM, Jörn Nettingsmeier wrote:
> > Patrick Shirkey wrote:
> >> I had a thought that maybe the network sound card should not be using
> >> ethernet but instead wireless 802.11n.
> >>
> >> The ralink rt2870 chipset is well supported at full 300Mb/s on Linux and
> >> has open source drivers.
> >>
> >> I think this would open up a lot of opportunities with a wireless sound
> >> card.
> >>
> >> I'm not sure how many are on the market right now but I haven't heard of
> >> any yet so there is a big opportunity there to fill a gap.
> >
> > low latency audio over wireless is fundamentally impossible.
> >
> > it's a shared medium, pretty much like thicknet or any other hub or bus
> > network. if two endpoints ever send at the same time (and they will),
> > the packets will clash and trigger resends after a non-deterministic
> > delay (so as to avoid endless re-clashing if two endpoints happen to be
> > "in sync").
> >
> > the only thing that would work over wireless is heavily-buffered media
> > center stuff for consumers, because nobody cares if there's half a
> > second delay between your pressing play and the start of the movie.
>
> So there's absolutely no way that a keyboard, pc, mixer, speaker set
> transferring data over 802.11n could be made to work?
>
> For example in a home studio setting...

There is no way to make it work with guaranteed low latency. You need somewhat
low latencies to play the keyboard to other music. And you need it guaranteed
unless you always record xruns and gaps as part of your musical experience...

And even then its wireless and using a frequency-range used by almost all
other people around you. Just count the wireless networks in your flat provided
you live in a flat with other people living upstairs/downstairs/next to you.
And then try to get a fast, non-interrupted stream (latency about 20ms or
shorter for real playing). And then remember Jörn in that it might be illegal
to shoot your neighbours...

Have fun,

Arnold

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Received on Wed Dec 23 12:15:05 2009

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