S/PDIF over 5.8GHz? AKA the Radio Party ;)

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   Report from the weekend at Shambala: works pretty damn well in the field! Range about 25-30m without dropouts, but if both systems are stationary it goes further. If you get into the beam of a powerful directional WiFi transmitter it drops out. Line of sight is a *must*, although the signal seems to travel through big hats, being worn by people walking between the rigs, quite well. Sound quality flawless, all fidelity of source preserved.Overall, lots of fun for not a lot of money as long as the occasional PHUT isn't going to ruin your performance!
Now my attention has been drawn to audio-over-WiFi systems...this way much spending lies, I fear.....but imagine if any next man could rock up, plug his phone into his rig, log on to your network and play your stream in sync for as far as the WiFi covers....now THAT would be a system!

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studio45 Members Profile Send Private Message Find Members Posts Add to Buddy List Old Croc Joined: 16 October 2007 Location: United Kingdom Status: Offline Points: 3864	Post Options Post Reply Quote studio45 Report Post Thanks(0) Quote Reply Posted: 03 September 2015 at 2:25pm
	Report from the weekend at Shambala: works pretty damn well in the field! Range about 25-30m without dropouts, but if both systems are stationary it goes further. If you get into the beam of a powerful directional WiFi transmitter it drops out. Line of sight is a must, although the signal seems to travel through big hats, being worn by people walking between the rigs, quite well. Sound quality flawless, all fidelity of source preserved. Overall, lots of fun for not a lot of money as long as the occasional PHUT isn't going to ruin your performance! Now my attention has been drawn to audio-over-WiFi systems...this way much spending lies, I fear.....but imagine if any next man could rock up, plug his phone into his rig, log on to your network and play your stream in sync for as far as the WiFi covers....now THAT would be a system!
	Studio45 - Repairs & Building Commotion Soundsystem -Mobile PA

shagnasty Members Profile Send Private Message Find Members Posts Add to Buddy List Old Croc Joined: 30 July 2007 Location: Guildford, UK Status: Offline Points: 7685	Post Options Post Reply Quote shagnasty Report Post Thanks(0) Quote Reply Posted: 03 September 2015 at 3:14pm
	Audio over Wifi has a few issues, first you will be using IP packets, there is nothing you can do to guarantee what order they arrive in, so that sucks, secondly if you need it sync'd you have to run JACK or a similar protocol, it is not as simple as slamming up an apache streaming server and logging in with Mediplayer or VLC, the Ethernet transport in general is the last place to put audio (hence Cobranet sucked so bad and I am yet to see the point in Dante over AES-50) but if you do it look at a couple of Beagle Bones with Berry UCA-202s plugged in, use 5Ghz wireless kit, Hide SSiD, MAC lock them and secure them, etc. do some trials with 2 VMs over a 10Meg Lan link first, don't worry about latency, as long as it is constant you can delay the source to it's PA to make the remote and source play in time...

studio45 Members Profile Send Private Message Find Members Posts Add to Buddy List Old Croc Joined: 16 October 2007 Location: United Kingdom Status: Offline Points: 3864	Post Options Post Reply Quote studio45 Report Post Thanks(0) Quote Reply Posted: 04 September 2015 at 5:08pm
	THat's really useful info, thanks man :) So I can see how to make a small box containing audio interfaces, a JACK server running on a BeagleBone, putting the stream out on WiFi and also locally for the transmitting rig, but what about recievers - everyone at the link-up rave is going to need a Bone of their very own, aren't they? Running the correct version of JACK-on-a-network, at that? I suppose the 12v sound community is one comprised largely of makers and inventors so it's moderately likely such things will be available, but still, an Android client was more what I was thinking of, for widespread usability. Otherwise I'd have to build a whole pack of Beagles and hope they didn't get nicked.....Then there's the Barix Instreamer/Exstreamer boxes that do it all in hardware and look really nice although would need a Wifi hub each and are a few more £.... Might do some experiments with stock phone hardware and less complicated audio streaming servers and see how bad the delay problem is. If it's less than 50mS we might just get away with it, although it's going to give DJ's a hard time beatmatching.
	Studio45 - Repairs & Building Commotion Soundsystem -Mobile PA

shagnasty Members Profile Send Private Message Find Members Posts Add to Buddy List Old Croc Joined: 30 July 2007 Location: Guildford, UK Status: Offline Points: 7685	Post Options Post Reply Quote shagnasty Report Post Thanks(0) Quote Reply Posted: 05 September 2015 at 3:11am
	Live boot a laptop with a USB stik to Linux build as a client machine for each rig, that way you just need a decent AP (I've used the HP 5Ghz ones with a fair amount of success) hung off your Beagle bone to uplink and then a lappy with a UCA-202 on for each system, just be aware even with line of sight big event will screw this, forget Yagi twigs, hi-gain twigs, you get 20 000 smart phone polling for APs it is all over, I have this every year @ IBC and MWC, all runs fine and then the punter walk in, each probably has 1.5 wifi devices on average active and you can't ping a thing... I've even had a building to building link running line of sight across a hall dump out on us and we had to get a fibre pulled in..... You should have no where near 50ms, but even 12-15mS will muddy up a bass line (don't forget process delay in LMS on top...) but if you program out any latency at least you have known starting point! Edited by shagnasty - 05 September 2015 at 3:14am

studio45 Members Profile Send Private Message Find Members Posts Add to Buddy List Old Croc Joined: 16 October 2007 Location: United Kingdom Status: Offline Points: 3864	Post Options Post Reply Quote studio45 Report Post Thanks(0) Quote Reply Posted: 04 June 2018 at 2:58pm
	Just thought I'd give this thread a little BUMP as I've recently posted this info on Facebook in the 12v sound groups there. After a couple of years of use, this system is still working exceptionally well. I never did try going to a fully Wifi-based setup, the time and money investment required was just too much. The only change I've made is to stop using 12v>USB converters to get 5v power, as most of them are just too noisy. So now I use a wiring harness with a 7805 regulator built in, to power the radio and digital converter at each end. All the minor buzzes and fuzzes are gone. I've also started using a preamp at each end - a simple unit that powers directly from battery voltage, to boost up quiet sources at the transmitter and recover the 6dB link loss at the receiver. Hope this is still useful information and can facilitate easy 12v link-ups (or any other kind of link up for that matter...wink wink) Join the Radio Party!
	Studio45 - Repairs & Building Commotion Soundsystem -Mobile PA

bitSmasher Members Profile Send Private Message Find Members Posts Add to Buddy List Old Croc Joined: 23 June 2012 Location: Melbourne Status: Offline Points: 2295	Post Options Post Reply Quote bitSmasher Report Post Thanks(0) Quote Reply Posted: 04 June 2018 at 11:11pm
	Really appreciate the detail posted on Facebook and here - thanks for sharing your knowledge
	https://www.instagram.com/batteryacidsoundsystem/

studio45 Members Profile Send Private Message Find Members Posts Add to Buddy List Old Croc Joined: 16 October 2007 Location: United Kingdom Status: Offline Points: 3864	Post Options Post Reply Quote studio45 Report Post Thanks(0) Quote Reply Posted: 16 July 2018 at 3:32pm
	A bug report - had a problem getting my mate into the Radio Party! A couple of weeks ago we had Sheffield Carnival, so naturally I went along to provide music in the parade, and decided to get my good friend james.folkes (ex-mod on here) to bring his battery-powered setup as well. It was to be mounted on a large electric cargo trike, much taller than my bike trailers, so it seemed to make sense to have his system as the transmitter and my two rigs as the receivers. Well, I just couldn't get it working for sh1t! For unknown reasons, having the transmitter attached to his (very similar) battery/power supply/amp setup instead of mine, caused the range to drop to less than 10 metres and loads of bad dropouts when moving around. I tried different S/PDIF cables, using my known-good transmitter/ADC instead of his, different antennas, different ways of generating +5v, the lot. Even got the sillyscope out to look at the S/PDIF waveforms at each end, they seemed fine. Just couldn't get any cooperation out of it at all. So to get thru the show, we had to switch to using the analogue audio channels, which gave vastly better range, but at the expense of audibly reduced bandwidth, coloured sound and lots of background hiss. I wouldn't want to use them the whole time, because when you're not playing music at full volume the hiss from the receiver is sooo bad. Plus of course, when you go out of range the system starts playing white noise at full whack. Put everything back to how it was originally (transmitting S/PDIF between the two bike trailers) and tried it out again at Middle Earth Dub Festival this weekend. Worked flawlessly again. Great sound, no dropouts and that good 30-50m range. I'm baffled. More experimentation is required. Please, someone else get a set of this radio gear, and tell me how you get on!
	Studio45 - Repairs & Building Commotion Soundsystem -Mobile PA