Network card Clock upgrade

[plissken]

A) not a mental exercise: [ATTACH]33692[/ATTACH]

B) not a static buffer

C) No USB

D) Maybe zero copy stack

 

What is that from? What is the PHY on it as it is most likely buffered itself? Do you know the OS running it?

 

It doesn't look like an Intel Pro 1000GT which is what this thread is about. If your board is driven by an RTOS and there is no buffering going on then maybe an upgraded clock will improve things. I doubt very highly that what you pictured is an running an RTOS and no buffering.

 

I noticed the Kingston on it. If that's DRAM then AudioQuest thinks that is the worst sounding RAM module out there.

[jabbr]

What is that from? What is the PHY on it as it is most likely buffered itself? Do you know the OS running it?

 

It doesn't look like an Intel Pro 1000GT which is what this thread is about. If your board is driven by an RTOS and there is no buffering going on then maybe an upgraded clock will improve things. I doubt very highly that what you pictured is an running an RTOS and no buffering.

 

I noticed the Kingston on it. If that's DRAM then AudioQuest thinks that is the worst sounding RAM module out there.

 

Correct is not an Intel Pro NIC ... to clarify I've never said that an Intel NIC could be casually improved so if we are limiting this s discussion to that then we are straying waaay off topic -- I don't use my 1000GTs for audio -- currently using x520s in most parts f my machines.

 

What you are seeing is a very highly integrated SoC that incorporates dual ARM and FPGA. There is extraordinary flexibility in handling Ethernet essentially allowing an SFP cage to be hung off the IO pins and the rest being handled on chip--or not. It runs Ubuntu Linux with a low latency kernel if that matters. Or FreeRTOS.

 

Clocks yes clocks it has clocks -- very good clocks -- no need to "upgrade"

[plissken]

Correct is not an Intel Pro NIC ... to clarify I've never said that an Intel NIC could be casually improved so if we are limiting this s discussion to that then we are straying waaay off topic -- I don't use my 1000GTs for audio -- currently using x520s in most parts f my machines.

 

What you are seeing is a very highly integrated SoC that incorporates dual ARM and FPGA. There is extraordinary flexibility in handling Ethernet essentially allowing an SFP cage to be hung off the IO pins and the rest being handled on chip--or not. It runs Ubuntu Linux with a low latency kernel if that matters. Or FreeRTOS.

 

Clocks yes clocks it has clocks -- very good clocks -- no need to "upgrade"

 

Agreed we are off topic. If someone wants to fart around with a NIC and solder on a new clock that's fine but it's not going to improve the Audio playback. We used to overclock the Motorola 680X0 series by soldering in a quicker Oscillator adding a heatsink.

[audiventory]

I use a SOTM sms-200 directly connected to my audio server. For the moment this sms-200 is connected to one of the two embedded network card of the mainboard of my server.

 

I have ordered a PCI-e network card (Intel Pro-1000 GT). I will use this network card to connect my sms-200. I would like to upgrade the clock of this network card with a better clock (TCXO, OCXO or something even better like for example a FEMTO clock).

 

I wonder if someone has already tried to upgrade the clock of a network card? I think that upgrading the clock of a network card should have the same impact as upgrading the clock in a USB card. I did some research on Google, but I’m surprised that I found nothing about that.

 

So, do you have experience with clock upgrade on a network card, and do you know what the frequency of the clock in a network card is?

 

 

Clock of network don't impact to DAC clock. Only DAC clock impact to sound quality (noise/distortions).

 

If you use network for playback 1080 and more resolution of movie, slow network can cause lags in movie.

 

For audio 100 Mbit network have too high speed for causing issues for playback high resolution audio stream.

 

If your network work wrong, you will hear pauses and/or clicks. Clock stability of network mean nothing, because DAC have own audio data buffer and own clock for reading from the buffer.

[jabbr]

I happened on while looking at something else today:

https://wiki.trenz-electronic.de/display/PD/TEB0745+TRM

 

This is a carrier board that has 8 SFP+ cages and a single RJ45 for Ethernet. You can see that the SFP+ cages are powered but the data pins go directly to the "SOM" which is a board like what I posted above that contains the ARM/FPGA "SoC" chip.

 

You can see that the entire Ethernet (and TCP/IP) stacks can be handled by this chip. Why would someone want to do that? Oh perhaps 10gbe layer 1 switch or line rate packet inspection. In any case I'm not using this board but the pictures in the link are really good at illustrating my point.

 

But anyways when we talk about being able to do 16 channels of DSD1024 or 32 of DSD512 (or higher with 10gbe) thats what I'm taking about. That's a piece of cake for this stuff. The fun stuff starts if I can also design an on chip phase error measurement system with sufficient resolution (the sufficient resolution is the hard part ;)

 

So if, when, I get this running and if I can measure phase error on an actual DAC clock (the clocks are being sent into the chip to control the FIFO already) then some of these speculations about blah, blah, blah tweak, clock, memory, SSD, power supply and cables actually affecting the sound (and here I mean the actual stream of bits in the DAC) can actually be tested.

 

Oh and A/BX, well with 32 channels I think that can be handled in "software" (actually programmable logic or "PL")

[Mihaylov]

Hi!

So, do you have experience with clock upgrade on a network card, and do you know what the frequency of the clock in a network card is?

 

Thanks in advance

 

CAT

[shoom]

Nice work Mihalov.

Looks like the sort of circuit I used to mod some of my CD players back in the day.

The Vanguard is a pretty nice clock which I’ve also used once or twice in the past.

What are you powering the XO with?

 

Some subjective thoughts on the Difference made if any would be great.

Thanks for sharing.

 

[Mihaylov]

What are you powering the XO with?

 

 

 

Dedicated linear PSU with SuperTeddyReg.

[shoom]

Nice

 

I've also used those Teddy's and more recently Tent Labs shunt which was also nice,

 

I have a spare in my parts box :-).

[plissken]

On 3/6/2017 at 6:13 AM, Mihaylov said:

 

Fortunately the extended 25 MHz accuracy is going go be rendered moot by Asynchronous FIFO. I have to point this out: That NIC is like the cheapest built NIC you can purchase. Comparatively it's junk to a $20 Intel NIC.  I would rather hit ServerSupply or Amazon and just get an Intel Server NIC that are pulls out of new systems where they replacing them with 10/25/40/100G NICS. They are super affordable ($18 for a dual port Intel Server NIC is common).

 

 

[Crom]

Here's my thoughts on this in case I can help the debate. I have been messing around with clocks and audio PC stuff for a few years and what might be relevant to this discussion is that my finding is that it's not always the quality/accuracy (etc) of the clock that provides the initial improvement, but rather the fact that the clock is separately powered.

 

It's true that the better the clock, the better the results but separately powering the clock (and the best I've found is by a lifepo battery) provides the best bang for buck.

 

I have changed the clock in this way, in pretty much everything I have in the 'signal' (or data) chain using exactly this method and I can't think off the top of my head where there hasn't been an improvement of one sort or another. Some examples, Compact flash adapter cards, motherboards, usb cards.

 

So, whereas logic might suggest this is a fool's errand, it's probably worth a couple of hours fiddling to give it a go and as the cards are so cheap to start with - buy two and A:B test.

[plissken]

3 hours ago, Crom said:

Here's my thoughts on this in case I can help the debate. I have been messing around with clocks and audio PC stuff for a few years and what might be relevant to this discussion is that my finding is that it's not always the quality/accuracy (etc) of the clock that provides the initial improvement, but rather the fact that the clock is separately powered.

 

It's true that the better the clock, the better the results but separately powering the clock (and the best I've found is by a lifepo battery) provides the best bang for buck.

 

I have changed the clock in this way, in pretty much everything I have in the 'signal' (or data) chain using exactly this method and I can't think off the top of my head where there hasn't been an improvement of one sort or another. Some examples, Compact flash adapter cards, motherboards, usb cards.

 

So, whereas logic might suggest this is a fool's errand, it's probably worth a couple of hours fiddling to give it a go and as the cards are so cheap to start with - buy two and A:B test.

 

 

Audio is cached. You can completely test the function of whether the externally powered clock is of importance by having someone start play back and while you are listening pull the Ethernet cable. You won't have to solder a thing and it won't cost a penny. So if your point is the external power then some one should get crackalacking on an external power supply for all three voltage busses (10, 100, 1000) as you won't even have to solder in a new clock at that point.

 

AGAIN...  The obvious elephant in the room: When the network cable is yanked during playback, and the system is still playing, What good is is 25Mhz clock with more zeros after the decimal point externally powered or otherwise? The Clock isn't even in use in this case. Is it somehow MORE 25Mhzrty?

 

The only thing the clock is there for is to sync up with the Ethernet port on the far end of the cable. There are two FIFO buffers on the NIC. One for the link and and one for what ever system bus (most often PCI).

 

Those realtek cards are still comparative pieces of shit to a $20-30 Intel Server NIC no matter the shade of lipstick you want to apply.

[jabbr]

10 hours ago, plissken said:

 

 

Audio is cached. You can completely test the function of whether the externally powered clock is of importance by having someone start play back and while you are listening pull the Ethernet cable. You won't have to solder a thing and it won't cost a penny. So if your point is the external power then some one should get crackalacking on an external power supply for all three voltage busses (10, 100, 1000) as you won't even have to solder in a new clock at that point.

 

AGAIN...  The obvious elephant in the room: When the network cable is yanked during playback, and the system is still playing, What good is is 25Mhz clock with more zeros after the decimal point externally powered or otherwise? The Clock isn't even in use in this case. Is it somehow MORE 25Mhzrty?

 

The only thing the clock is there for is to sync up with the Ethernet port on the far end of the cable. There are two FIFO buffers on the NIC. One for the link and and one for what ever system bus (most often PCI).

 

Those realtek cards are still comparative pieces of shit to a $20-30 Intel Server NIC no matter the shade of lipstick you want to apply.

Nice video post. Properly explains subltlies like "greycodes". 

 

Haha, well my system doesn't work with the network yanked so there...

 

I totally agree that starting out with a POS NIC is a "suboptimal" way to spend a differential of $10 for an Intel.

 

The clock has to, you know, be within the designed spec in terms of "jitter" which affects setup times etc. so I can see how a bad clock could exceed tolerances and cause actual bit errors e.g. flops capturing on a transition etc. I can also see how ground noise and noisy PSUs could cause clocks to exceed specifications. I agree that as long as things are "within spec" that it shouldn't matter and looking into this, don't think that since the 1980s, that we've made any real progress in diminishing noise etc. The Intel stuff, even a previous generation or two available for $20, has terrific performance and, yeah, I'd be impressed if any casual tweaks could improve.

 

That said, I keep an open mind.

[audiventory]

That asychronous FIFO placed in any DAC, as far as I know. Also such FIFO placed in audio player software/firmware.

 

Length of the buffer define delay between coming data to DAC and rising signal at audio output.

 

For home audio applications the delay is almost no matter.

[greenleo]

On 2017/3/24 at 5:30 PM, Crom said:

 

...

So, whereas logic might suggest this is a fool's errand, it's probably worth a couple of hours fiddling to give it a go and as the cards are so cheap to start with - buy two and A:B test.

This is how I view CAS as well.  I still remember in the 80's when CD just came out, people were arguing that logically CD should sound better than vinyl?