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Post by bluemeanies on May 1, 2016 8:06:43 GMT -5
Here is an article from PS Audio I thought would be of interest to people who are listening to their music via computer.
I left this road of persuit for music once I was introduced to TIDAL.
Hope this article opens people's horizons for good sound.
The LANRover
I have been hinting about a special device that improves the sound of USB audio for some time. Now it’s time to let the cat out of the bag.
When you connect your computer to your DAC through USB there’s a lot of problems getting the sound right. This is because your computer is a hostile environment for delivering clean audio data. Think of your computer like a noisy crowd and the music like a lone musician trying to be heard at a cocktail party. It’s near impossible unless you separate him from the crowd.
One trick you can use is to connect the computer through a USB hub, using two USB cables–one between the computer and the hub, the other between the hub and the DAC. While it may seem counter intuitive to improve something by adding another element in the data path, it works. In fact, the idea of a purpose built USB hub is what the famous Uptone Regen essentially does – and it works well – improving audio in every case. A USB hub, like the Regen, offers a degree of isolation between the computer and the DAC, though it’s not complete. Think of this degree of isolation as a doorway separating the noisy crowd (our computer). Our beleaguered musician is close to the open door and we hear him more clearly than before.
If we wish to remove even more of our imagined crowd noise, we can filter it by adding something like the AudioQuest Jitterbug for even clearer sound.
But if we want to eliminate the crowd noise altogether we need a completely new approach. Enter the LANRover.
The PS Audio LANRover leverages network protocols to fully isolate the computer’s crowd noise from the music. The LANRover employs two boxes: one connects to your computer, the other to your DAC. Between the two boxes a computer cable, commonly known as a CAT5, is used. The miracle of this technique is the near 100% isolation between the noisy computer and the quiet needs of a DAC.
By converting the USB data into packetized network data we get two major benefits. First, near perfect isolation cutting the computer’s crowd noise and jitter levels so effectively the level would be acceptable in a quiet library. And that has HUGE sonic benefits. Second, once converted to network audio, as opposed to directly connected USB audio, we can place a great deal of distance between the two boxes if we want to–the computer can be anywhere in the house and connect to your DAC anywhere else. We can do this even over WIFI. Imagine your computer’s no longer in the listening room, but upstairs in the office where it belongs. Bingo!
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Post by wilburthegoose on May 1, 2016 9:48:18 GMT -5
I'm not with you. Music data sent out of a PC is digital in the same way all data sent to a USB device is digital. We don't need special devices when we copy non-music data files from a PC to a USB device - why should we require it for music?
For me, the DAC in my XMC-1 works great, and I have no reason to switch.
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Post by audiosyndrome on May 1, 2016 18:55:46 GMT -5
The LANrover is not a DAC; it's an USB streaming bridge. It galvanically isolates the computers USB port from your DAC by attaching the same with two LANrover modules and an ethernet cable between the modules. This should provide better sound quality (subjective). Also, a big deal, the computer and DAC can be located any practical distance from each other. 100 feet no problemo. Currently USB is limited to approximately 16 feet.
Russ
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Post by bluemeanies on May 1, 2016 19:38:10 GMT -5
I'm not with you. Music data sent out of a PC is digital in the same way all data sent to a USB device is digital. We don't need special devices when we copy non-music data files from a PC to a USB device - why should we require it for music? For me, the DAC in my XMC-1 works great, and I have no reason to switch. I did not write the article. Paul McGowan from PS Audio is the author. Also it is not an article that I expect people to agree or disagree. It's information that people may want to use. |
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KeithL
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Post by KeithL on May 2, 2016 16:52:05 GMT -5
Since Ethernet is a PACKET BASED system, by sending USB over Ethernet they are totally discarding the original clock and substituting the clock generated by the receiving device. Therefore, the clock will be as good or bad as the clock in that device - period. (So, yes, it is a reclocking device.) And, since they are generating an entirely new signal, and they say they are galvanically isolating the power, then the power will be as good (or bad) as the power provided by that device. However, here's the real question....... If you're going to take some device - like a computer - and play audio via USB...... Why would you want to then run that USB output through a bunch of interface extenders to another USB device at the other end of some long wire? If your "source" has an Ethernet input, then you might as well just move it to the other end - near your USB DAC. And, try as I might, I can't think of any source devices that put out USB but DON'T have an Ethernet input (other than phones and portable players). The LANrover is not a DAC; it's an USB streaming bridge. It galvanically isolates the computers USB port from your DAC by attaching the same with two LANrover modules and an ethernet cable between the modules. This should provide better sound quality (subjective). Also, a big deal, the computer and DAC can be located any practical distance from each other. 100 feet no problemo. Currently USB is limited to approximately 16 feet. Russ |
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KeithL
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Post by KeithL on May 2, 2016 17:16:13 GMT -5
There really seems to be some serious missing of basic points here...... We're playing music on a computer...... So the music starts out as either packets on a network (streaming) or data on a hard disc. The computer then decodes that data if necessary, then send sit out of its USB port to a DAC for conversion to audio. So, instead of doing it this way, we're going to take the USB data from the computer..... Turn it BACK into network packet data... Send that packet data over a wire.... Then convert it BACK into USB audio data again.... THEN send it to our USB DAC.... So, what we really have is a data re-clocker (which could possibly help - although any decent USB DAC should be doing this already on its own).... And a wire extender..... Wouldn't it be easier just to put your player (whatever it is) down at the other end next to the DAC... and use a DAC with a good quality asynch USB input (so it wouldn't need reclocking)? Honestly, the only way I can see much use for this would be if it's cheaper than the other current USB extender solutions (which run $200 to $300 per 100 feet).... and you really need to put a DAC in some isolated location where you can;t put your computer next to it. And, "if your computer's upstairs in the office where it belongs", then are you planning to run up there every time you want to change songs.....? And, if you're planning to use another computer as a remote control for THAT computer, then wouldn't it be easier to just play the music on the one you're using for a remote control.....? Here is an article from PS Audio I thought would be of interest to people who are listening to their music via computer. I left this road of persuit for music once I was introduced to TIDAL. Hope this article opens people's horizons for good sound. The LANRover I have been hinting about a special device that improves the sound of USB audio for some time. Now it’s time to let the cat out of the bag. When you connect your computer to your DAC through USB there’s a lot of problems getting the sound right. This is because your computer is a hostile environment for delivering clean audio data. Think of your computer like a noisy crowd and the music like a lone musician trying to be heard at a cocktail party. It’s near impossible unless you separate him from the crowd. One trick you can use is to connect the computer through a USB hub, using two USB cables–one between the computer and the hub, the other between the hub and the DAC. While it may seem counter intuitive to improve something by adding another element in the data path, it works. In fact, the idea of a purpose built USB hub is what the famous Uptone Regen essentially does – and it works well – improving audio in every case. A USB hub, like the Regen, offers a degree of isolation between the computer and the DAC, though it’s not complete. Think of this degree of isolation as a doorway separating the noisy crowd (our computer). Our beleaguered musician is close to the open door and we hear him more clearly than before. If we wish to remove even more of our imagined crowd noise, we can filter it by adding something like the AudioQuest Jitterbug for even clearer sound. But if we want to eliminate the crowd noise altogether we need a completely new approach. Enter the LANRover. The PS Audio LANRover leverages network protocols to fully isolate the computer’s crowd noise from the music. The LANRover employs two boxes: one connects to your computer, the other to your DAC. Between the two boxes a computer cable, commonly known as a CAT5, is used. The miracle of this technique is the near 100% isolation between the noisy computer and the quiet needs of a DAC. By converting the USB data into packetized network data we get two major benefits. First, near perfect isolation cutting the computer’s crowd noise and jitter levels so effectively the level would be acceptable in a quiet library. And that has HUGE sonic benefits. Second, once converted to network audio, as opposed to directly connected USB audio, we can place a great deal of distance between the two boxes if we want to–the computer can be anywhere in the house and connect to your DAC anywhere else. We can do this even over WIFI. Imagine your computer’s no longer in the listening room, but upstairs in the office where it belongs. Bingo! |
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Post by yves on May 2, 2016 17:58:48 GMT -5
There really seems to be some serious missing of basic points here...... We're playing music on a computer...... So the music starts out as either packets on a network (streaming) or data on a hard disc. The computer then decodes that data if necessary, then send sit out of its USB port to a DAC for conversion to audio. So, instead of doing it this way, we're going to take the USB data from the computer..... Turn it BACK into network packet data... Send that packet data over a wire.... Then convert it BACK into USB audio data again.... THEN send it to our USB DAC.... So, what we really have is a data re-clocker (which could possibly help - although any decent USB DAC should be doing this already on its own).... And a wire extender..... Wouldn't it be easier just to put your player (whatever it is) down at the other end next to the DAC... and use a DAC with a good quality asynch USB input (so it wouldn't need reclocking)? Honestly, the only way I can see much use for this would be if it's cheaper than the other current USB extender solutions (which run $200 to $300 per 100 feet).... and you really need to put a DAC in some isolated location where you can;t put your computer next to it. And, "if your computer's upstairs in the office where it belongs", then are you planning to run up there every time you want to change songs.....? And, if you're planning to use another computer as a remote control for THAT computer, then wouldn't it be easier to just play the music on the one you're using for a remote control.....? Here is an article from PS Audio I thought would be of interest to people who are listening to their music via computer. I left this road of persuit for music once I was introduced to TIDAL. Hope this article opens people's horizons for good sound. The LANRover I have been hinting about a special device that improves the sound of USB audio for some time. Now it’s time to let the cat out of the bag. When you connect your computer to your DAC through USB there’s a lot of problems getting the sound right. This is because your computer is a hostile environment for delivering clean audio data. Think of your computer like a noisy crowd and the music like a lone musician trying to be heard at a cocktail party. It’s near impossible unless you separate him from the crowd. One trick you can use is to connect the computer through a USB hub, using two USB cables–one between the computer and the hub, the other between the hub and the DAC. While it may seem counter intuitive to improve something by adding another element in the data path, it works. In fact, the idea of a purpose built USB hub is what the famous Uptone Regen essentially does – and it works well – improving audio in every case. A USB hub, like the Regen, offers a degree of isolation between the computer and the DAC, though it’s not complete. Think of this degree of isolation as a doorway separating the noisy crowd (our computer). Our beleaguered musician is close to the open door and we hear him more clearly than before. If we wish to remove even more of our imagined crowd noise, we can filter it by adding something like the AudioQuest Jitterbug for even clearer sound. But if we want to eliminate the crowd noise altogether we need a completely new approach. Enter the LANRover. The PS Audio LANRover leverages network protocols to fully isolate the computer’s crowd noise from the music. The LANRover employs two boxes: one connects to your computer, the other to your DAC. Between the two boxes a computer cable, commonly known as a CAT5, is used. The miracle of this technique is the near 100% isolation between the noisy computer and the quiet needs of a DAC. By converting the USB data into packetized network data we get two major benefits. First, near perfect isolation cutting the computer’s crowd noise and jitter levels so effectively the level would be acceptable in a quiet library. And that has HUGE sonic benefits. Second, once converted to network audio, as opposed to directly connected USB audio, we can place a great deal of distance between the two boxes if we want to–the computer can be anywhere in the house and connect to your DAC anywhere else. We can do this even over WIFI. Imagine your computer’s no longer in the listening room, but upstairs in the office where it belongs. Bingo! Bingo!  |
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Post by garbulky on May 2, 2016 22:25:48 GMT -5
If they are doing ethernet traensmission. Why are they sending it over USB first? I can undertsand ethernet to USB - maybe. But I don't see why they can't go eternet to an ethernet DAC? Why go USB in the first place?
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Post by yves on May 3, 2016 3:10:58 GMT -5
If they are doing ethernet traensmission. Why are they sending it over USB first? I can undertsand ethernet to USB - maybe. But I don't see why they can't go eternet to an ethernet DAC? Why go USB in the first place? It's because, to be Hi Res playback capable, most USB DACs on Windows require device drivers to be installed I guess, but there exist numerous software solutions (including some pretty good/reliable ones in fact) that allow USB ports to be shared over an ethernet connection. However, this will only work fluently if the other network traffic isn't monopolizing all your bandwidth, and, to be able to ensure this, you can add software like e.g. NetLimiter, and/or use an ASUS ethernet switch that comes with a socalled "VIP Port":  |
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Post by qdtjni on May 3, 2016 4:02:25 GMT -5
Honestly, the only way I can see much use for this would be if it's cheaper than the other current USB extender solutions (which run $200 to $300 per 100 feet).... and you really need to put a DAC in some isolated location where you can;t put your computer next to it. And, "if your computer's upstairs in the office where it belongs", then are you planning to run up there every time you want to change songs.....? And, if you're planning to use another computer as a remote control for THAT computer, then wouldn't it be easier to just play the music on the one you're using for a remote control.....? Even though other USB extenders can use Cat5/6/7 cabling, I don't if any of the can use an existing LAN with IP already in place that would also allow for switches, routers, etc, at least not for USB Audio. Hence it might have to be a direct cable from the computer playing music. So if one want to extend USB for any reason, using IP could certainly be beneficial. As for controlling the player in a remote computer, what about LMS infrastructure or Roon from a tablet, smartphone, browser, VNC, etc? After all, that has been possible with Squeezeboxes (or rather Slim Device 2001. Then one might ask why bother with USB at at all when a small player can have network connectivity and DAC in the same box and then use i2S internally instead. Again Slim Devices have been doing this since 2001 although I must say, Roon gives a way better user experience and also works with other devices such as Roon enabled devices, Macs, Linux Windows, AirPlay and more. |
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Post by qdtjni on May 3, 2016 4:11:15 GMT -5
If they are doing ethernet traensmission. Why are they sending it over USB first? I can undertsand ethernet to USB - maybe. But I don't see why they can't go eternet to an ethernet DAC? Why go USB in the first place? One reason would be to re-use an existing DAC. |
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Post by wilburthegoose on May 3, 2016 6:16:03 GMT -5
to me, this is analogous to the infamous green magic marker on a CD.
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Post by yves on May 3, 2016 6:56:30 GMT -5
If they are doing ethernet traensmission. Why are they sending it over USB first? I can undertsand ethernet to USB - maybe. But I don't see why they can't go eternet to an ethernet DAC? Why go USB in the first place? One reason would be to re-use an existing DAC. Dollar per dollar, asynchronous USB done right gives better audio performance than ethernet. So it's essentially a "no frills" philosophy, which I, like many other people, greatly prefer. |
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Post by qdtjni on May 3, 2016 7:06:57 GMT -5
One reason would be to re-use an existing DAC. Dollar per dollar, asynchronous USB done right gives better audio performance than ethernet. So it's essentially a "no frills" philosophy, which I, like many other people, greatly prefer. Done right a music player reading data over an IP network negates the need for USB and sounds better, i2S done right easily beats USB any day. EDIT: Corrected typos. |
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Post by audiosyndrome on May 3, 2016 8:36:56 GMT -5
So my question is when will the XMC-1 be able to accept music via the ethernet port from my Mac mini ? Other than loading the Dirac filters, the port has no place in life.  Russ |
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KeithL
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Post by KeithL on May 3, 2016 9:10:31 GMT -5
You're missing the basic "technology point" here.... Digital audio data consists of data (bits) and a clock. The ONLY factors that affect "the sound quality of a digital audio signal" are whether the correct bits arrive at the destination at the correct times. And, once the digital audio arrives at the DAC, it's up to the DAC to do a good job of converting the digital audio into analog audio. As far as the output is concerned, all that matters is that the data is correct and the clock is good WHEN IT IS RECEIVED AT THE DAC CHIP ITSELF.
BOTH Ethernet and USB are "packet mode" communications, and so BOTH require that the data be re-clocked when it is received. With USB, the computer sends the data itself synched to a rather poor version of the clock; older USB devices "locked onto" this clock and "regenerated" it, which resulted in a pretty poor quality clock; asynchronous USB devices generate their own clock, and the quality of that clock depends solely on the clock circuitry in the device. The packets sent over Ethernet don't contain the clock at all; so a brand new clock much be created by the receiving device to go with them. In both cases, the quality of the clock is determined entirely by the receiving device - which is what's generating the clock that's used to convert the audio data. In the old days, when the clock sent by the source device was used to clock the actual conversion, the quality of the resulting audio was dependent on the quality of that clock. However, in any Ethernet packet system, or asynch USB system, since a totally new clock is created by the receiving device, that's the ONLY clock that matters. (And, if the DAC itself re-clocks the data, then all that matters is the quality of the clock used to do so.) Which device sounds better is simply a matter of which device generates a better clock (and of how good the DAC itself is). Most DACs (both USB and Ethernet) use i2S internally to send the audio signal between the receiver circuitry and the DAC itself. i2S is a "short haul" protocol used to carry the audio between various circuit modules inside DACs; it works quite well over short distances, but very poorly over long distances. (i2S and USB are rarely, if ever, used for the same purposes.... so there's not much point in comparing them.) "Galvanic isolation" is a whole different issue - and relates to preventing noise on the ground and power supply lines of the source device from making its way into the DAC. Fully isolating the source from the DAC is always a good idea - although it may not always make an actual difference. (Incidentally, Toslink is totally isolated, as are many Coax digital inputs.) There is no inherent difference in "sound quality" between USB and Ethernet; both are simply ways of getting digital data from one place to another. Any differences you hear are strictly due to how well a specific device of either sort does its job. (And I would most certainly expect a $500+ device of either type to do an excellent job  ) Dollar per dollar, asynchronous USB done right gives better audio performance than ethernet. So it's essentially a "no frills" philosophy, which I, like many other people, greatly prefer. Done right a music player reading data over an IP network negates the need for USB and sounds better, i2S done right easily beats USB any day. EDIT: Corrected typos. |
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KeithL
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Post by KeithL on May 3, 2016 9:11:36 GMT -5
While it's possible somewhere down the road, we have no immediate plans to implement audio streaming via Ethernet inside the XMC-1. So my question is when will the XMC-1 be able to accept music via the ethernet port from my Mac mini ? Other than loading the Dirac filters, the port has no place in life. Russ |
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Post by qdtjni on May 3, 2016 9:23:02 GMT -5
With all due respect, you are the one missing the point here. IP -> i2S is better than USB -> IP -> USB -> i2S, everything else being equal. EDIT: The sound difference is more theoretical than that one would hear it, IMHO. EDIT2: Even with a local player, i.e. not using a device similar to the on OP described, you would have IP -> USB -> USB -> i2S, the IP -> i2S is simpler the good sense |
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Post by wilburthegoose on May 3, 2016 9:34:17 GMT -5
Isn't it just data? Shouldn't make any difference at all. You think your local hospital ICU "wires" their instrumentation differently than ethernet/usb/encrypted wireless? PS - I may be wrong  |
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Post by qdtjni on May 3, 2016 9:37:43 GMT -5
Isn't it just data? Shouldn't make any difference at all. You think your local hospital ICU "wires" their instrumentation differently than ethernet/usb/encrypted wireless? A lot, maybe even most hospital grade equipment relies on extra layers of galvanic insulation on top of that built into standard Ethernet, so to answer your question, yes they do.  |
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