Actually, 802.11at Type 2 supports up to 25w, but requires more effort to source power. That is, newer more costly, switches or insertors. The hack you describe isn't really so hack-ish, since there are a number of non-802.11 compliant approaches to POE. Including one that's capable of delivering up to 90 watts. Here's a unique approach called Digital Electricity. https://voltserver.com/ They provide high-power and data over a simple 2-conductor pair. They claim 20x the power and distance of 802.11af solutions. Cost is another matter.
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 --------- Subject: Re: [Sursound] Multichannel players for permanent installations From: "Marc Lavallée" <m...@hacklava.net> Date: 6/29/17 11:48 am To: sursound@music.vt.edu The limit is actually more like 13W per device, according to: https://fr.wikipedia.org/wiki/Alimentation_%C3%A9lectrique_par_c%C3%A2ble_Ethernet A Raspberry Pi and a DAC would use 5 to 6W, leaving 7-8W to a D-amp. With efficient loudspeakers (and a few of them), 6W could enough for a small public installation. A hackish alternative would be to use only 2 pairs of a CAT5 cable for a 100BT link (which is enough to stream audio), and use the 2 other pairs to transmit power (as much as required). Running speaker wires is also a valid solution... -- Marc On Thu, 29 Jun 2017 09:10:12 -0700, mgra...@mstvp.com wrote: > Hi, > > This is an interesting discussion. Common, 802.3af P.O.E. is limited > to 15w. Fine for a Raspberry Pi, DAC or DSP, but not enough for much > amplification. > > 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 --------- Subject: Re: [Sursound] > Multichannel players for permanent installations From: "Dave Hunt" > <davehuntau...@btinternet.com> Date: 6/29/17 11:04 am > To: sursound@music.vt.edu > > Hi, > > I think that you'll find that an active speaker with an AVB input > will require more current than can be supplied over an ethernet > cable. Perhaps for very small speakers with a low power digital > amplifier, but anything decent would require mains (or DC batteries) > to the speaker. > > The available current may power the DAC though. > > Ciao, > > Dave > > > From: Augustine Leudar <augustineleu...@gmail.com> > > Date: 28 June 2017 22:06:52 BDT > > To: Surround Sound discussion group <sursound@music.vt.edu> > > Subject: Re: [Sursound] Multichannel players for permanent > > installations > > > > > > Hi Richard - > > There is lots of things that pan all around the room but the > > soundscape is > > designed in pre production for this installation and then its just > > a multichannel file (or seperate mono ones). Other installations I > > do are > > interactive and so sounds are processed and panned in realtime > > around the > > space depending on the sensors used etc. Certainly the AVB thing > > might be > > good for some less inhospitable environments- I especially like > > the way > > power can be taken to the the speakers via the ethernet > > cable..... > > -------------- next part -------------- > An HTML attachment was scrubbed... > URL: > <https://mail.music.vt.edu/mailman/private/sursound/attachments/20170629/0e011d85/attachment.html> > _______________________________________________ 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. > -------------- next part -------------- An HTML attachment was > scrubbed... URL: > <https://mail.music.vt.edu/mailman/private/sursound/attachments/20170629/3bffefc0/attachment.html> > _______________________________________________ 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. -------------- next part -------------- An HTML attachment was scrubbed... URL: <https://mail.music.vt.edu/mailman/private/sursound/attachments/20170629/0f09417f/attachment.html> _______________________________________________ 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.
