A novel way to massively improve the SQ of computer audio streaming

[marce]

15 hours ago, JohnSwenson said:

Grounding the output opens the possibility of a good old fashioned ground loop (magnetic induction from hot wires to ground wire causing voltage difference between branches of the electrical wiring or long distances on the same circuit). But not grounding lets the high impedance leakage pass through to the output.

 

Nobody else even seems to be looking at high impedance leakage, I didn't even know about it until two months ago. It is so high an impedance that normal test equipment shorts it to ground and you never see it. The problem is that its effects ARE showing up in audio systems (not all and not in the same way in all systems, of course it can't be anything simple). I had to build my own test equipment to even see it.

 

A good part of the problem is that almost all the original work on leakage currents took place many years before the advent of SMPS so they were just looking at linear power supplies, which don't have the high impedance leakage. Its a fairly recent issue, significantly exacerbated by computers and computer networks involved in our audio systems. (since these almost always use SMPS)

 

John S.

Class 1 or class 2 SMPS's or on both?

[ElviaCaprice]

On ‎10‎/‎15‎/‎2017 at 6:50 AM, octaviars said:

@ElviaCaprice on your Jetway mobo I see that SOtM modded it to three external clock points do you know what clocks they replaced? I only thought a mobo had one clock for the system and one clock for the ethernet connection but it seems that there is a third one? In the manual for the SOtM sCLK-EX they show a picture of a mobo and a tX-USBexp and they only use three clock points for the mobo AND the  tX-USBexp.

 

I have been searching for a mobo that might work well to modify and also have M.2 for OS (Windows, Roon), SATA for my SSD (music) and a PCIe connector for the tX-USBexp. Found this but I dont really have a clue if it is any good and would work with this setup  

 

https://www.minipc.de/catalog/il/1409

 

After inquiring with May, I have more answers about what exactly they replaced for clocks on my Jetway NUC.  Main system clock, LAN (both we're done) and the USB (I would assume all of the inputs). 

May thinks that by replacing the USB and LAN clocks it helps improve the SQ of the mobo even if not using these clocks directly for the audio stream. 

Therefore, I stand corrected and my hasty judgement of the SOtM's own server which is not all that different technically, as far as the clocking goes.  Still price wise your paying a hefty premium for this server over a DIY of your own.

 

Hopefully others are in the process of doing their own sCLK-EX DIY servers and we shall get some other impressions soon.

[Johnseye]

2 hours ago, ElviaCaprice said:

 

After inquiring with May, I have more answers about what exactly they replaced for clocks on my Jetway NUC.  Main system clock, LAN (both we're done) and the USB (I would assume all of the inputs). 

May thinks that by replacing the USB and LAN clocks it helps improve the SQ of the mobo even if not using these clocks directly for the audio stream. 

Therefore, I stand corrected and my hasty judgement of the SOtM's own server which is not all that different technically, as far as the clocking goes.  Still price wise your paying a hefty premium for this server over a DIY of your own.

 

Hopefully others are in the process of doing their own sCLK-EX DIY servers and we shall get some other impressions soon.

 

How many sCLK-EX taps were used for the mobo alone and what were the frequencies? I assume 1 for system, 1 for both NICs but what about the USB? 

[afrancois]

19 hours ago, JohnSwenson said:

YES, the grounding on the negative of the supply feeding the switch shunts the high impedance leakage coming from the network. So if using an LPS-1 you must ground the OUTPUT so the negative going into the switch is properly grounded.

 

John S.

I have an AQVOX switch that has its chassis grounded. An LPS-1 is powering this switch.

I grounded the output of the LPS-1 but I did not hear any difference. Could it because I'm using a network isolator (EmoSafe EN-30) between the switch and the sMS-200 ultra?

 

[austinpop]

54 minutes ago, Johnseye said:

 

How many sCLK-EX taps were used for the mobo alone and what were the frequencies? I assume 1 for system, 1 for both NICs but what about the USB? 

 

I expect 24MHz for USB and 25MHz for Ethernet. So that's 2.

 

Many mobo's also use 25MHz, so then the question remains whether the same 25Mhz clock tap can be shared to drive both the mobo and the Ethernet. But there may be other considerations that require a separate clock tap for the mobo. 

 

I seem to remember @ElviaCaprice saying as much, but it will be good to get his confirmation.

[austinpop]

I wanted to mention an interesting nugget of information Eric and I got during a sit-down with Lee at RMAF. This is in the context of using an sCLK-EX tap to synthesize the sample data frequencies of 22.5792 MHz and 24.576 MHz.

 

I mention this just in case someone is designing an end-to-end setup, and running out of clock taps for some reason.

 

Here's the factoid: Lee mentioned that with sample data frequencies, they can reprogram a single clock tap on the fly to switch between the 2 frequencies. They do this by using a control feedback loop of some kind, where they can detect the sample rate of an impending incoming data stream, and send a control "set the right frequency" signal to the sCLK-EX board.

 

Caveat: due to the language barrier, I can only describe this in very broad terms - I could not glean the details of the feedback loop mechanism.

 

But the application, in whose context he mentioned it, was the use of essentially one clock tap for both 22.5792 MHz and 24.576 MHz in the dX-USBultra.

 

I have no idea if this concept can be used to pack multiple frequencies for other uses. I only mention it as a "good to know" data point.

 

Caveat emptor.

[Summit]

20 hours ago, JohnSwenson said:

The switches mentioned are only 1/100 switches so cannot handle gigabit Ethernet. If you need gigabit for other devices go ahead and run them through a separate gigabit switch, using the FS108 or FS105 on a connection to the audio device.

 

I did not spend a lot of time trying all kinds of different configurations, in my tests I had the FS105 etc with just two connections, one to my main gigabit switch and one to the streamer. That does not mean that is the only configuration that will work, just that I didn't test any other configurations.

 

One thing I did find is that it is important to leave an empty port next to the one going to the endpoint. For example if the endpoint is on port 1, don't plug anything into port 2. (its actually more complex than that, sometimes you CAN plug something in next to the endpoint connection, but always leaving the ports next to it free will guarantee you don't have a problem).

 

John S.

 

Do you have any explanation or theory to why it’s better to leave an empty port next to the one going to the endpoint?

[ElviaCaprice]

20 minutes ago, austinpop said:

 

I expect 24MHz for USB and 25MHz for Ethernet. So that's 2.

 

Many mobo's also use 25MHz, so then the question remains whether the same 25Mhz clock tap can be shared to drive both the mobo and the Ethernet. But there may be other considerations that require a separate clock tap for the mobo. 

 

I seem to remember @ElviaCaprice saying as much, but it will be good to get his confirmation.

I didn't ask May which was which.  But I am using 3 points off the sCLK-EX, one set to 12MHz, the other 2 to 25MHz (at different voltage???)  So now I am going to have to ask may what the 12MHz point was used on???

[Johnseye]

14 minutes ago, austinpop said:

 

I expect 24MHz for USB and 25MHz for Ethernet. So that's 2.

 

Many mobo's also use 25MHz, so then the question remains whether the same 25Mhz clock tap can be shared to drive both the mobo and the Ethernet. But there may be other considerations that require a separate clock tap for the mobo. 

 

I seem to remember @ElviaCaprice saying as much, but it will be good to get his confirmation.

 

I thought it was different taps for the system and ethernet, at least that's what Roy said was done with his board.  

 

1 minute ago, austinpop said:

I wanted to mention an interesting nugget of information Eric and I got during a sit-down with Lee at RMAF. This is in the context of using an sCLK-EX tap to synthesize the sample data frequencies of 22.5792 MHz and 24.576 MHz.

 

I mention this just in case someone is designing an end-to-end setup, and running out of clock taps for some reason.

 

Here's the factoid: Lee mentioned that with sample data frequencies, they can reprogram a single clock tap on the fly to switch between the 2 frequencies. They do this by using a control feedback loop of some kind, where they can detect the sample rate of an impending incoming data stream, and send a control "set the right frequency" signal to the sCLK-EX board.

 

Caveat: due to the language barrier, I can only describe this in very broad terms - I could not glean the details of the feedback loop mechanism.

 

But the application, in whose context he mentioned it, was the use of essentially one clock tap for both 22.5792 MHz and 24.576 MHz in the dX-USBultra.

 

I have no idea if this concept can be used to pack multiple frequencies for other uses. I only mention it as a "good to know" data point.

 

Caveat emptor.

 

This would be nice if possible, but is there any cost or impact to the sound?

 

My dilemma is whether to buy a tx-USBultra's sCLK (3 free clocks) for my motherboard and the tx-USBexp or to buy an sCLK and not the tx-USBultra for the motherboard, tx-USBexp and a switch, or in a worst case scenario I need all 4 clocks for the motherboard and tx-USBexp.  I don't want to have to buy a tx-USBultra and an sCLK.

[elan120]

28 minutes ago, austinpop said:

I wanted to mention an interesting nugget of information Eric and I got during a sit-down with Lee at RMAF. This is in the context of using an sCLK-EX tap to synthesize the sample data frequencies of 22.5792 MHz and 24.576 MHz.

 

I mention this just in case someone is designing an end-to-end setup, and running out of clock taps for some reason.

 

Here's the factoid: Lee mentioned that with sample data frequencies, they can reprogram a single clock tap on the fly to switch between the 2 frequencies. They do this by using a control feedback loop of some kind, where they can detect the sample rate of an impending incoming data stream, and send a control "set the right frequency" signal to the sCLK-EX board.

 

Caveat: due to the language barrier, I can only describe this in very broad terms - I could not glean the details of the feedback loop mechanism.

 

But the application, in whose context he mentioned it, was the use of essentially one clock tap for both 22.5792 MHz and 24.576 MHz in the dX-USBultra.

 

I have no idea if this concept can be used to pack multiple frequencies for other uses. I only mention it as a "good to know" data point.

 

Caveat emptor.

@austinpop, good information indeed.  Based on my limited conversation with SOtM and some additional research for modding my SU-1, only one output tab is needed from sCLK-EX to switch between two frequencies, and the control inputs on sCLK-EX board are the SEL0 and SEL1.  They can, based on the two available input connections, program two different output tabs with two frequencies, so if I can get all the information needed from SOtM to make the project a go, I will be using one of the four output tabs along with SEL0 to control between 22.5792MHz and 24.576MHz outputs.

[Johnseye]

12 minutes ago, elan120 said:

@austinpop, good information indeed.  Based on my limited conversation with SOtM and some additional research for modding my SU-1, only one output tab is needed from sCLK-EX to switch between two frequencies, and the control inputs on sCLK-EX board are the SEL0 and SEL1.  They can, based on the two available input connections, program two different output tabs with two frequencies, so if I can get all the information needed from SOtM to make the project a go, I will be using one of the four output tabs along with SEL0 to control between 22.5792MHz and 24.576MHz outputs.

 

Does this introduce a manual switch or something that automatically knows when a specific frequency is being used?  If manual it limits the number of devices or clocks per sCLK-EX board.  If auto then what's the limit?

[elan120]

1 minute ago, Johnseye said:

 

Does this introduce a manual switch or something that automatically knows when a specific frequency is being used?  If manual it limits the number of devices or clocks per sCLK-EX board.  If auto then what's the limit?

The mentioned SEL0 and SEL1 input connections will do the auto frequency switching.  My understanding on the frequency limit is two per output tab, but there need to have a control signal feed into the sCLK-EX SEL0 and SEL1 inputs in order to do the switching.

[austinpop]

45 minutes ago, ElviaCaprice said:

I didn't ask May which was which.  But I am using 3 points off the sCLK-EX, one set to 12MHz, the other 2 to 25MHz (at different voltage???)  So now I am going to have to ask may what the 12MHz point was used on???

 

12MHz is likely for USB. Exact sub-multiple of the 480 Mb/s rate. Some interfaces seem to want 24 MHz, which goes back to the reason why the sCLK-EX is programmable!

[austinpop]

8 minutes ago, Johnseye said:

 

Does this introduce a manual switch or something that automatically knows when a specific frequency is being used?  If manual it limits the number of devices or clocks per sCLK-EX board.  If auto then what's the limit?

 

Just now, elan120 said:

The mentioned SEL0 and SEL1 input connections will do the auto frequency switching.  My understanding on the frequency limit is two per output tab, but there need to have a control signal feed into the sCLK-EX SEL0 and SEL1 inputs in order to do the switching.

 

Since the incoming data is on USB, i.e. an independent clock unrelated to the sample rate clock, as long as the device can read enough info off the stream to determine if the sample rate is of the 44.1 or 48 kHZ family, it has enough information to program the sCLK-EX clock tap appropriately, using the signals @elan120 mentions.

 

Please do let us know how your SU-1 experiments go!

[octaviars]

4 hours ago, ElviaCaprice said:

Hopefully others are in the process of doing their own sCLK-EX DIY servers and we shall get some other impressions soon.

 

I am planing a server with Win10, AO and Roon right now with the same Jetway NF591 mobo as @Johnseye has planned to get modified by SOtM, really looking forward to what they do to it.

So perhaps it is 3 clocks for the mobo (system, LAN and USB) like @ElviaCaprice had done for his mobo and use the leftover clock for the tX-USBexp? My first plan was to use one clock for my router but I dont know if I want to go down that route, perhaps focusing on the server is a better thing?

 

Regarding the tX-USBexp is there a prefered voltage on the external input (6,5-9Vdc)? And perhaps the same goes for the sCLK-EX with 9Vdc (Standard), optional 12Vdc and optional 6.5Vdc ~ 8.5Vdc which one is the prefered voltage (I know May says it is system dependant)?

 

 

[rickca]

6 hours ago, ElviaCaprice said:

May thinks that by replacing the USB and LAN clocks it helps improve the SQ of the mobo even if not using these clocks directly for the audio stream. 

I'd like to understand why SOtM thinks that replacing clocks that aren't used could contribute to better sound quality.

[rickca]

3 hours ago, austinpop said:

Lee mentioned that with sample data frequencies, they can reprogram a single clock tap on the fly to switch between the 2 frequencies.

Oh good,  because this wasn't complicated enough before.

[elan120]

2 hours ago, austinpop said:

 

 

Since the incoming data is on USB, i.e. an independent clock unrelated to the sample rate clock, as long as the device can read enough info off the stream to determine if the sample rate is of the 44.1 or 48 kHZ family, it has enough information to program the sCLK-EX clock tap appropriately, using the signals @elan120 mentions.

 

Please do let us know how your SU-1 experiments go!

Will do.  I have enough information to do the SU-1 mod using sCLK-EX, but still trying to gather information on what to do with the computer mobo.  I know there is going to be one output to the system clock, one to LAN, and one to tX-USBexp card, but unclear on what other clock(s) to replace, and additionally, what is the output connection used, as I see different pictures from SOtM sCLK-EX instruction manual using an output PCB, but various pictures from this thread that has no output PCB.  Hopefully I can get them to respond what the differences are, and what I need to do to install them.  Once this is understood, I will get the kits to modify both my computer as well as SU-1.

 

 

1 hour ago, octaviars said:

 

I am planing a server with Win10, AO and Roon right now with the same Jetway NF591 mobo as @Johnseye has planned to get modified by SOtM, really looking forward to what they do to it.

So perhaps it is 3 clocks for the mobo (system, LAN and USB) like @ElviaCaprice had done for his mobo and use the leftover clock for the tX-USBexp? My first plan was to use one clock for my router but I dont know if I want to go down that route, perhaps focusing on the server is a better thing?

 

 

I am curious about this as well.  I thought if you use tX-USBexp card, there will be three clocks (system, LAN, and tX-USBexp), not sure if there is a need for the USB clock replacement.

[Johnseye]

3 minutes ago, rickca said:

Oh good,  because this wasn't complicated enough before.

 

Yea, is it accurate, why wasn't it explained before, why didn't Roy mention it and did he use it in his build.  This info comes just in time for me.  Hopefully it helps.

 

8 minutes ago, rickca said:

I'd like to understand why SOtM thinks that replacing clocks that aren't used could contribute to better sound quality.

 

Very good question.  It doesn't sound logical unless you actually use the USB ports of the server if the USB card is using PCIe lanes.

[octaviars]

6 hours ago, ElviaCaprice said:

Main system clock, LAN (both we're done) and the USB (I would assume all of the inputs). 

 

Well that was what I also thought but as the system above uses 3 clocks for the mobo and one for the USB card I really dont know. Time will tell how they do with the Jetway NF591.

 

2 minutes ago, elan120 said:

I thought if you use tX-USBexp card, there will be three clocks (system, LAN, and tX-USBexp), not sure if there is a need for the USB clock replacement.

 

[rickca]

9 minutes ago, Johnseye said:

Yea, is it accurate, why wasn't it explained before, why didn't Roy mention it and did he use it in his build.  This info comes just in time for me.  Hopefully it helps.

Note that this idea of using one clock tap to switch between frequencies applies only to sample data frequencies, so it doesn't apply to anything on your motherboard or tX-USBexp where nothing runs at sample data frequencies.

 

I'm quite confused about the voltage options for sMS-200Ultra ... 6.5v-8.5v, 9v or 12v.  Obviously, you want 6.5-8.5 if you want to use an LPS-1.  Does it filter better/differently at 9v or 12v?  The same voltage options are available on the sCLK-EX.

 

 

[Johnseye]

3 minutes ago, rickca said:

Note that this idea of using one clock tap to switch between frequencies applies only to sample data frequencies, so it doesn't apply to anything on your motherboard or tX-USBexp where nothing runs at sample data frequencies.

 

 

 

I didn't realize that.  Then what's the point?

[JohnSwenson]

3 hours ago, Summit said:

 

Do you have any explanation or theory to why it’s better to leave an empty port next to the one going to the endpoint?

I don't have details on this, but it seems to be related to many switches using dual magnetics modules. These have two channels in one box. If the two connections are on the same magnetics box then leakage is not blocked. If the connections are on different magnetics boxes then leakage IS blocked.

 

A possible mechanism is that a box has one connection from transformer center taps to the ground plane. If going between magnetics boxes the leakage current HAS to go through whatever method is used to connect the box to the ground plane. If the connections are on the same magnetics box then this network that connects to the ground plane is bypassed.

 

Which port to port connections get properly leakage blocked depends on which ports go through which magnetic boxes. You don't really know unless you open up the switch and look.

 

FREQUENTLY, but not always, port 1 and 2 are on the same, port 2 and 3 are on the same etc. For a 5 port it may be different, 1 and 2 may be on the same OR 4 and 5 may be on the same, which means 1 and 2 are on different magnetics boxes.

 

The way to make sure you don't into this issue is to keep the ports next to the one connected to the audio system unconnected. So if you put the cable going to the audio system on the first or last port and put the one next to it unconnected you are almost certainly good.

 

John S.

[rickca]

14 minutes ago, Johnseye said:

 

I didn't realize that.  Then what's the point?

This new information about switching sample data frequencies is applicable if you are modding something like an SU-1 that has SPDIF output.  Recall that with SPDIF the clock is encoded into the data stream, unlike USB.

[lmitche]

27 minutes ago, Johnseye said:

 

Yea, is it accurate, why wasn't it explained before, why didn't Roy mention it and did he use it in his build.  This info comes just in time for me.  Hopefully it helps.

 

 

Very good question.  It doesn't sound logical unless you actually use the USB ports of the server if the USB card is using PCIe lanes.

Maybe a clockectomy is better, and cheaper.