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I love the idea of high fidelity, active, wireless speakers, and a transceiver source-control hub... ️

Krunok

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#41
Wifi and speakers are both old technologies. They haven't been traditionally incorporated mostly because there's not much benefit for most people. There's nothing particularly forward-thinking about sticking them together in the same box IMHO.

What do you see as the benefit?
Dali solution is based on Bluetooth APTX HD, not WiFi. While there's plenty of bandwidth available with WiFi no audio transport standard was ever developed. On the other hand, BT, however bandwidth constrained, seems to be the winner in this race as APTX is evidently evolving while also beeing widely accepted by manufacturers.
 

Krunok

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#42
I think the important part is active speakers can get rid of the passive crossovers and slip in some DSP based EQ. The wireless feature is mainly lifestyle.
You're obviously not married, otherwise you would be fully aware about your wife's opinion on wires in the rooms! :D
 

andymok

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#43
Yes, but not until 802.11ad 60Ghz that travels nothing more than a few meters with line-of-sight.

Wireless is wireless in the sense of the last mile.

While I'm sure that is a vision shared by many people, one of the reason it didn't gain popularity could simply because it is just unreliable, so unreliable that no one dares to guarantee the result at all, unless you make it as a system, in return greatly limited the application/usage. Certainly hurt a lot, be it R&D or potential market reach.

Wireless Speaker Synchronization: Solved
http://www.aes.org/e-lib/browse.cfm?elib=17878

"Digital wireless audio systems are technically challenging to implement. For example, many highend stereo systems offer a ‘party mode’ where several devices are linked together to play the same audio stream to create a multi-room experience. However sometimes the network is unreliable, perhaps the environmental conditions for Wi-Fi are unfavourable, or the location of the transmitter is unsuitable. Networked audio devices rely upon a master clock to keep them all synchronized. If that clock signal is lost or delayed due to insufficient bandwidth or intermittent network communications then ‘party mode’ rapidly degrades into a jumbled cacophony of sound. The timing problem is even more critical when considering multi-channel wireless speaker systems, such as those organized as stereo pairs or in building 5.1 configurations for surround sound.

One of the main difficulties in synchronizing streams over TCP/IP networks is that they employ ‘best effort’ methods to deliver IP packets – there’s no guarantee of delivery and packets can arrive randomly, albeit within a reasonably predicable timeframe. Even using timestamped multicast streams, clients will drift out of synchronization and need to be periodically corrected. In the case of audio-visual stream delivery, the inherent latency within the network is often too large and unpredictable to reliably synchronize streams between several client devices. Whilst it’s true that software time-stamping protocols running over TCP/IP can provide some degree of synchronization between pairs of devices, these methods have to factor in network latency and round-trip packet times and are therefore not fine-grained enough for audio, especially when maintaining separation between stereo audio channels or recreating perfect 5.1 surround sound. "

An Evaluation Tool for Wireless Digital Audio Applications (old, but you get the idea)
http://www.aes.org/e-lib/browse.cfm?elib=13102

"While the wireless transmission protocol employed provides QoS service guarantees, it is evident that significant reproduction distortion may be introduced, due to the non-ideal nature of the wireless channel, which may cause lack of data in the reception buffers or packet overflows in the transmission queue. Moreover, playback distortions induced only in one audio stream, can lead to out-of-phase reproduction between channels, as shown in the example test case. "

And of course, I can't recommend this paper more, from TI

Challenges in 2.4 GHz Wireless Audio Streaming
http://www.aes.org/e-lib/browse.cfm?elib=16075
 
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andymok

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#44
Dali solution is based on Bluetooth APTX HD, not WiFi. While there's plenty of bandwidth available with WiFi no audio transport standard was ever developed. On the other hand, BT, however bandwidth constrained, seems to be the winner in this race as APTX is evidently evolving while also beeing widely accepted by manufacturers.
Point-to-Point / One-to-One / PAN (Personal Area Network) / Unicast is easy
Many-to-Many / LAN / Multicast is hard lol
 

Krunok

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#45
Point-to-Point / One-to-One / PAN (Personal Area Network) / Unicast is easy
Many-to-Many / LAN / Multicast is hard lol
I'm just looking at my D-Link DIR-885L WiFi router which, at this very moment, handles one 8Mb/s video stream of "Antman and the Wasp" from NAS to the kids room and the other 8Mb/s video stream to the sleeping room where my wife is watching some other movie. At the same time my notebook is downloading a large file from the Net with speed of app 15Mb/s, so I'm wondering where exactly do you see a problem with HiRes audio streaming with current 802.11ac technology?
 

BillG

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#46
Wow, does that mean your phone supports APTX HD? :)
Mine does. However, since the original aptX offered near CD transparency when streamed to quality hardware, I have to listen carefully in order to hear difference between it and the HD variant - I notice a bit more dynamic range and slightly cleaner sound. For casual listening it's unnoticeable...
 

Krunok

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#47
Mine does. However, since the original aptX offered near CD transparency when streamed to quality hardware, I have to listen carefully in order to hear difference between it and the HD variant - I notice a bit more dynamic range and slightly cleaner sound. For casual listening it's unnoticeable...
Original APTX actually offered mp3 alike quality while APTX HD is 48kHz/24 bit. I do agree that for casual listening APTX is indeed quite acceptable.
 

BillG

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#48
I'm wondering where exactly do you see a problem with HiRes audio streaming with current 802.11ac technology?
Someone was yammering on about Wifi radio frequency bands becoming increasingly crowded, which is true and will become even more so with the explosion of the Internet of Things paradigm. However, I live in an urban environment filled with Wifi enabled devices and have yet to experience an actual problem caused by radio frequency interference - I stream and beam all day every day. So I think the developers of these transmission standards know what they're doing... :cool:
 

BillG

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#49
Original APTX actually offered mp3 alike quality while APTX HD is 48kHz/24 bit. I do agree that for casual listening APTX is indeed quite acceptable.
I'm well aware of what it offers having worked in software engineering for my entire adult life, being immersed in mobile technology for nearly as long, and being a music lover, who happened to study recording engineering briefly, for even longer... :cool:
 

Krunok

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#50
I'm well aware of what it offers having worked in software engineering for my entire adult life, being immersed in mobile technology for nearly as long, and being a music lover, who happened to study recording engineering briefly, for even longer... :cool:
In that case you are aware that main problem with APTX is that it has to encode at the source and decode at the receiver. Although APTX is comparable to mp3 and APTH HD to CD I haven't really seen measured implications of encoding mp3 to APTX and decoding it back to mp3. The same same will of course happen when you send 24/48 or 16/44.1 FLAC over APTX HD.
 

Krunok

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#51
Someone was yammering on about Wifi radio frequency bands becoming increasingly crowded, which is true and will become even more so with the explosion of the Internet of Things paradigm. However, I live in an urban environment filled with Wifi enabled devices and have yet to experience an actual problem caused by radio frequency interference - I stream and beam all day every day. So I think the developers of these transmission standards know what they're doing... :cool:
5GHz from your neighbours won't really cause you any problems unless you live in an extremely dense populated building with thin walls. On the other hand, modern WiFi technologies like MU MIMO and beam forming have been proven to be effective.
 

maverickronin

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#52
I'm just looking at my D-Link DIR-885L WiFi router which, at this very moment, handles one 8Mb/s video stream of "Antman and the Wasp" from NAS to the kids room and the other 8Mb/s video stream to the sleeping room where my wife is watching some other movie. At the same time my notebook is downloading a large file from the Net with speed of app 15Mb/s, so I'm wondering where exactly do you see a problem with HiRes audio streaming with current 802.11ac technology?
The primary issue is latency, not bandwidth. Wifi's latency is not only higher, but also extremely variable. When the audio and video are all in one stream, going from point A to point B with a little buffering and decoded all at once at point B that doesn't matter so much.

When you're trying to keep several different devices syncronized it get harder to design and become more sensitive to interference necessitating retransmitting packets.

It also depends on what you're using the speakers for. Just playing straight music rarely has any trouble. The is plenty of bandwidth in modern wireless protocols and latency won't be a concern. If the audio needs to match up with video then latency becomes an issue unless you don't mind losing lipsync. If each individual speaker is wireless then keeping them all in sync will take even more work.
 

andymok

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#53
Actually, I think in the end this will be more like a subtopic in IoT. Right now we have a host(source), feeding data to client controller (FPGA, DSP...) to instruct various subsystem and do the heavy work (channel routing, eq, mapping rendering) for us. What would it be like when we have a headless system/many-head system?

https://iot.ieee.org/newsletter/march-2017/three-major-challenges-facing-iot.html

And don't forget meshing, if wireless is the trend, mesh network will be the next standard. And that only get things even more complicated with routing decisions.
 
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Krunok

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#54
The primary issue is latency, not bandwidth. Wifi's latency is not only higher, but also extremely variable. When the audio and video are all in one stream, going from point A to point B with a little buffering and decoded all at once at point B that doesn't matter so much.

When you're trying to keep several different devices syncronized it get harder to design and become more sensitive to interference necessitating retransmitting packets.

It also depends on what you're using the speakers for. Just playing straight music rarely has any trouble. The is plenty of bandwidth in modern wireless protocols and latency won't be a concern. If the audio needs to match up with video then latency becomes an issue unless you don't mind losing lipsync. If each individual speaker is wireless then keeping them all in sync will take even more work.
Take a look at Denon HEOS solution, I'm using it for some time now and it works just fine.

I don't know exactly how it works but I guess multichannel stream is sent via WiFi to the decoder unit via which then feeds separate channels it's own network. It's definitely a propriatery solution but the audio interface is UPnP/DLNA.
 
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Sal1950

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#55
You're obviously not married, otherwise you would be fully aware about your wife's opinion on wires in the rooms! :D
Since it possible to get rid of the wife and not the wires, there is only one currently viable answer to you statement. :D

As to wireless speakers, in the real "here and now" I'd just as soon run the speaker wire or interconnect as a AC line.
A whole lot of much "ado about nothing".
And leaving out the WAF bit, even if battery powered wifi were viable, untill we get to a point where the battery would only need charging once a month or less I'd still stick to a wire. Even today I'm so sick of having to remember to pull in my cell phone, outdoor boombox, it's mated MP3 player and a couple other each night. BLAH
I still keep around a wired drill and hedgetrimmer. Tired of going to use one only to find the battery dead or no longer charges due to being a few years old. The AC line at least is reliable. ;)
 

Krunok

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#56
Since it possible to get rid of the wife and not the wires, there is only one currently viable answer to you statement. :D
You can get rid of both of them, but I believe the true question here is which one is cheaper to get rid of. :D

As to wireless speakers, in the real "here and now" I'd just as soon run the speaker wire or interconnect as a AC line.
Good point. As Ethernet over powerline products work really well I see no reason why not to go that path.
 

maverickronin

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#57
I don't know exactly how it works but I guess multichannel stream is sent via WiFi to the decoder unit via which then feeds separate channels it's own network. It's definitely a propriatery solution but the audio interface is UPnP/DLNA.
Without digging into the manuals their website is short on details, but it probably does use a proprietary protocol to stream in between and sync everything.

My point isn't that it can't work, just that environmental conditions make it less reliable in the long term, especially with typical home installations. You never know when enough interference from you neighbors will pile up start impacting you range, making the ones farther away flaky.

I do IT for a living and this is a fairly common problem. Someone works from home, has their computer and even printer on the wifi, and eventually they notice the connection gets slower and less reliable. Once that happens you're at least going to have to run a wire for another AP. If you're running wires to something that's already wired anyway (for power at least) why insist on the last few feet being wireless?

I've been using using wifi since 802.11b and have seen the 2.4GHz spectrum in my neighborhood get more and more crowded every year. A cheap consumer router in the basement used to reach to the opposite corner of the second floor just fine. Now an entry-level-enterprise AP in the center of the first floor can't even reach that same room reliably. It will still stream 4K perfectly fine to the nearby Roku, but who knows how long that will last before I need 2 APs just to cover the first floor.

Good point. As Ethernet over powerline products work really well I see no reason why not to go that path.
I've had to replace those with proper CAT6 runs as well when the power in the neighborhood got dirtier over time. I haven't seen one in several years now though. Don't know if that means they're better or just less popular.
 

Thomas savage

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#58
You can get rid of both of them, but I believe the true question here is which one is cheaper to get rid of. :D



Good point. As Ethernet over powerline products work really well I see no reason why not to go that path.
For the ultimate WAF one needs to downgrade to a speaker with high cabinet resonance at just the right frequency and just the right amplitude.
 

Krunok

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#59
Without digging into the manuals their website is short on details, but it probably does use a proprietary protocol to stream in between and sync everything.

My point isn't that it can't work, just that environmental conditions make it less reliable in the long term, especially with typical home installations. You never know when enough interference from you neighbors will pile up start impacting you range, making the ones farther away flaky.

I do IT for a living and this is a fairly common problem. Someone works from home, has their computer and even printer on the wifi, and eventually they notice the connection gets slower and less reliable. Once that happens you're at least going to have to run a wire for another AP. If you're running wires to something that's already wired anyway (for power at least) why insist on the last few feet being wireless?

I've been using using wifi since 802.11b and have seen the 2.4GHz spectrum in my neighborhood get more and more crowded every year. A cheap consumer router in the basement used to reach to the opposite corner of the second floor just fine. Now an entry-level-enterprise AP in the center of the first floor can't even reach that same room reliably. It will still stream 4K perfectly fine to the nearby Roku, but who knows how long that will last before I need 2 APs just to cover the first floor.
Central unit uses it's own AP to stream to satellite speakers, not your WiFi AP.

I've had to replace those with proper CAT6 runs as well when the power in the neighborhood got dirtier over time. I haven't seen one in several years now though. Don't know if that means they're better or just less popular.
They got better.
 

maverickronin

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#60
Central unit uses it's own AP to stream to satellite speakers, not your WiFi AP.
That would probably give you more stability at the expense of range. Not a bad tradeoff if you aren't scattering them over the entire house.

They got better.
If they're better at filtering out line noise then there will plenty of room for these to grow before they run into interference on their own transmission frequencies since they aren't very popular.
 
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