Originally published at: Run audio to speakers through your home's power lines - Boing Boing
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I’m a little curious to know how far these types of systems will transmit the data. Is there something that stops it from going upstream of the power meter? If not, what’s to prevent neighbors from tapping into it as well?
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long long ago (oh… late 70s maybe? and likely FM) there were “home intercom” systems that used the powerlines for their audio signal. My father thought that was neat. Until we started to hear conversations from a neighbor easily a block away (rather sexy at times as this adolescent at the time vaguely recalls). My father stopped using it immediately. Perhaps these have some sort of ‘security’ added…? [shrug]
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If it’s anything like the ethernet-over-powerline arrangements it does not cope well with going through transformers(ethernet over powerline doesn’t really seem to cope well in general; but sometimes you have to work with the copper you’ve got) so you get some intrinsic isolation that way(sometimes also between parts of your own house; depending on how it was wired); and homeplug or G.hn boxes also encrypt the chatter between themselves since the medium is considered untrusted.
Compared to wifi, which as the marketshare, I suspect that G.hn doesn’t get the coolest cryptographers and most intense scrutiny of implementations; but it’s not just screaming in plaintext.
If anything; given that this box specifically states digital audio support only; it would be pretty unsurprising to find that there’s just normal powerline networking gear inside, with just an audio-specific bridge to the outside world. You could certainly do it other ways; but failing to exploit commodity parts is generally a bad move in niche gear unless you can command absolutely crazy prices.
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Wait, do these things have amps in them? Maybe I’ve misread the article; I can’t quite get the source-to-speaker relationship.
Yeah, I get that but not every residence gets its own individual transformer, especially in apartment buildings. But perhaps it is encrypted as you suggest.
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Yes; from the article:
the receivers plug into power outlets and have standard positive/negative red and black speaker cable terminals for wiring to a speaker, plus an RCA output for subwoofers.
According to Fasetto, receivers have an integrated class D amplifier that’s rated for 100 watts at 2 Ohms, 60 watts at 4 Ohms, and 40 watts at 8 Ohms.
Class D amps aren’t generally known for their audio quality but sometimes tickle the boundaries of high end.
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Hahaha, absolutely
What, however, if your household power lines happen to be gold-plated, eh?
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All you need to do is to put a brick on top of the speaker just so and voila - high end!
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Thank you. In my situation, the HDMI input factor seems to be a real constraint, but with some re-wiring I could get it to work. Rob was right, It’s an appealing product.
Many moons ago a company I worked for made video processing boxes called Video Bricks:
About the size and weight of a half brick. The power cable was wired in, so you could swing them around with it.
At trade shows a running joke was that the head sales guy should take complaining customers to the conference room on the booth and er… ‘deploy’ said device to convince them that their concern was unwarranted 
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I use this for data like @beschizza used to. I don’t like wireless and I have a big unwired house. I do have to unplug and re-plug a few times a year to reset everything. Not sure if that’s from these or something else on my network.
I have a friend who would not consider these due to security concerns–data leakage at power system edge, etc
I went and looked to see if they encrypt and found that they can–but apparently if you don’t configure them they’ll be using the default key. I’ll go fix this when I get home.
I could see these being useful for some speaker installations. But I doubt they’ll be as reliable as plain old speaker wire. It’d be obnoxious if they ever need to be restarted to fix a problem the way I do for my data network. If you have to open up the wall to run power for your installation, you want to run speaker wire too.
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Why is there no audio in the video! Haha,
I’ve been looking around for something like a commercial version of this!
Since P.A. speakers are largely all going “powered” instead of “passive”, it means running BOTH a power and audio cable to each speaker. It would be great to run JUST a power cable that doubles as transmission line for the audio. Line arrays probably do this somehow, but it’s above my pay grade.
Ethernet over Powerline can be done, but it still requires a little “networked media player” for each speaker. The extra pile of adapters required makes it look easier in the long run to just run speaker cable and use centralized power amps.
I’d want to be able to set the audio receiver devices to have a default configuration (to set which channel that speaker would listen to on powerup) which could be altered remotely so the speakers can be re-assigned on the fly. It would have either a web server aboard the module, like any cheap home router, or at minimum a config utility on a host pc somewhere else on the network.
What would clinch the deal is if the modules also acted as a DMX bridge so lighting and effects could be run through the same network. Then get the manufacturers to build the audio recievers into the speakers so all anyone would ever have to do is place the speakers and run their AC to them!
The company I work for does something like this, but it’s still just ethernet, power delivery is separate, it does allow remote configuration of channels, etc, but doing professional audio over ethernet you end up sticking with tried and true hardware and components.
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… but if the audio is riding on switched packets rather than raw analog voltage, it’s not obvious how one would synchronize all these smart speakers with each other 
In the case of the real product from the article, I’d guess that the music stream is buffered, and speakers will watch a clock signal of some kind to make sure that packets will be played at the microsecond they were intended for.
In the case of a big P.A. system in a night club or outdoor event, speakers being a few microseconds off from each other is less of a problem. Though you still want to avoid that.
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