Marc, <apologies for being off topic>
Some time ago I agreed to give a trade show presentation about Polycom's HDVoice codecs (Siren 7, Siren 14) being released under a license making it possible to use them with the asterisk open source telephone software. In the way of dog-fooding the presentation, I tried to deliver it via an HDVoice capable BT headset (Plantronics Savvy Go) to a soft phone, relayed over a SIP link to the house PA. All on local LAN. The latency inherent to that path made it completely impractical if I was in the same room as the audience. I learned the hard way that local wireless should not be an IP-based link. Packetization delay is a killer. <lurker mode = on> Michael Graves mgra...@mstvp.com http://www.mgraves.org o(713) 861-4005 c(713) 201-1262 sip:mgra...@mjg.onsip.com skype mjgraves -----Original Message----- From: Sursound <sursound-boun...@music.vt.edu> On Behalf Of Marc Lavallée Sent: Tuesday, May 28, 2019 12:40 PM To: sursound@music.vt.edu Subject: Re: [Sursound] wifi audio (was Re: Deconstructing soundbar marketing B.S.) Le 28/05/2019 à 13:20, mgraves mstvp.com a écrit : > Marc, > > I'm well and truly intimate with WebRTC. The trouble with IP-based > connectivity is then latency involved with packetization. Then my hack would not be useful if you need reatime connectivity. For a good quality 256Kps Opus stream (24bit, 48Khz), latency was ~130ms with a 2.4Mhz wifi connection. Maybe it could be improved. > DECT and BT links don't suffer this, but they tend to be bandwidth > constrained (especially microphone freq response.) > > It's surprising that there are very few headsets with full bandwidth > microphone. Those that are, like the DPA D:Fine service, are offered for > stage/theatrical performance. They assume separate belt-packs for microphone > vs monitoring. The market share is probably too small; most wireless headsets are now being used with phones. Marc > > Michael Graves > mgra...@mstvp.com > http://www.mgraves.org > o(713) 861-4005 > c(713) 201-1262 > sip:mgra...@mjg.onsip.com > skype mjgraves > > -----Original Message----- > From: Sursound <sursound-boun...@music.vt.edu> On Behalf Of Marc > Lavallée > Sent: Tuesday, May 28, 2019 10:37 AM > To: sursound@music.vt.edu > Subject: [Sursound] wifi audio (was Re: Deconstructing soundbar > marketing B.S.) > > Le 28/05/2019 à 10:48, mgraves mstvp.com a écrit : > >> Marc, >> >> This is very interesting to me. Did you do this using Wi-Fi or some other >> wireless scheme? >> >> What I've been seeking is a low-cost, low-latency wireless solution for a >> headset. >> >> We have good, full-bandwidth solutions for wireless microphones. Also for >> wireless performance monitors. Nothing that combines these functions. > Hi Michael. > > My hack was not bidirectional (it could be), but I suspect that the WebRTC > standard could be used on a phone, a small standalone computer or some of the > newest iOT micro-controller with Wifi and full-duplex audio. > I have no idea how "better" it would be compared to available Bluetooth > headsets. And it would not be cheaper... A good start would be to design an > Android WebRTC app for your specific use case, and maybe this app already > exist. > > Marc > >> Michael Graves >> mgra...@mstvp.com >> http://www.mgraves.org >> o(713) 861-4005 >> c(713) 201-1262 >> sip:mgra...@mjg.onsip.com >> skype mjgraves >> >> -----Original Message----- >> From: Sursound <sursound-boun...@music.vt.edu> On Behalf Of Marc >> Lavallée >> Sent: Tuesday, May 28, 2019 7:20 AM >> To: sursound@music.vt.edu >> Subject: Re: [Sursound] Deconstructing soundbar marketing B.S. >> >> Last year I hacked a "low latency" (~100ms) stereo RTP streaming >> software between OSX and a Raspberry Pi. A possible solution would >> be, as Bo Erik suggested, to stream 4-channel on a musticast wifi >> network, then decode it on 4 RPIs (or similar boards), making sure >> they are in sync (using PTP). This is on my long list of things to >> try, but I would need a specific project to kick-start this >> exploration. I'm in the process of setting up a 4-channel system in >> my home office (using two >> 2.1 DIY "multimedia" system), so it's a good start. We could wait for the >> industry to provide something usable, but it would be proprietary, >> "professional", and expensive (because of the super-specific gold-plated >> hardware, patents, shareholders, marketing, logos, slick web sites, >> religious beliefs, etc). Also (who knows) maybe it's already possible to do >> it using the jack2 software suite. >> >> Marc >> >> Le 28/05/2019 à 07:40, Augustine Leudar a écrit : >>> Weve tried local wifi networks at shows before but it was a bit >>> unreliable for droppouts etc then again so is Bluetooth. FOr home us it >>> would be fine. >>> Four plug sockets might be a bit more doable than audio cables as well. >>> Wasn't there someone on here who was doing something DIY with the >>> rasberry pie ? Anyway it would nice to bring something commercially viable >>> to market. >>> >>> On Tue, 28 May 2019 at 09:39, Bo-Erik Sandholm <bosses...@gmail.com> wrote: >>> >>>> The Speakers won't be wireless as you probably want them to be powered. >>>> >>>> But it should be easy with bluetooth 4.0 or Wi-Fi direct to create >>>> a solution. >>>> >>>> Normal Wi-Fi could be used. >>>> The low cost esp8266 makes this possible in a diy setup... >>>> >>>> Stream a 4 channel audiostream to the 4 speakers. >>>> Have a switch on each speaker to select which channel it will playback. >>>> >>>> Could possibly be solved by streaming 2 stereo channels on 2 >>>> different ip ports over WiFi instead. 😎 >>>> >>>> Bo-Erik > _______________________________________________ > Sursound mailing list > Sursound@music.vt.edu > https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit > account or options, view archives and so on. > _______________________________________________ > Sursound mailing list > Sursound@music.vt.edu > https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit > account or options, view archives and so on. _______________________________________________ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on. _______________________________________________ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
