AIR1 v AIR2 v Spark

[ThierryNK]

Hi

As Magagne has already tested the configuration that I asked Ian to check, did someone test the "optical bridge"?

Ethernet Interfaces should all have galvanic isolation, for safety reasons. It is a norm. But it has been shown that high frequencies EMI pass through this galvanic isolation. Maybe Davialet Ethernet does not have this galvanic isolation or a very weak one.

I already evaluated several solutions for galvanic isolation as Giso:
http://www.audiophile-magazine.com/bancs...seau-giso/
And also filtering ethernet cable from Totaldac:
http://www.totaldac.com/ethernet_cable-eng.htm

But the most efficient is an optical bridge.
Optical bridge has already solved the noise issue on Devialet as seen on the link I posted in an earlier post.

The investment is not too expensive, about 100€  including a battery. 

You need 2 media converters of this kind:
http://www.ldlc.com/fiche/PB00103085.html

And one monomode SC/SC optical fiber as:
http://www.ldlc.com/fiche/PB00089183.html

Setup is quite straightforward.

Switch or computer
Ethernet cable
Media converter
Optical fiber
Media converter
Ethernet cable
Devialet

I also use a 5V battery on the media converter that is connected to the audio gear, to avoid the EMI of the switching power supply of this media converter that will go through ethernet. As this one:
https://www.amazon.fr/gp/product/B00N9W5...UTF8&psc=1
With this cable:
https://www.amazon.fr/gp/product/B00DELC...UTF8&psc=1

Initially, this kind of stuff is to filter EMI coming through ethernet to improve the noise level inside a streamer.

Apparently, there is something bad coming through ethernet that makes Devialet behave badly.
This cannot be "computer clock" because ethernet transmission happens in the range of 10 MHz which not the frequency of the audio signal (same for USB) .

Filtering ethernet is mandatory in health gears as scanners or MRI to avoid electrically killing people. 

Also use cat5e well shielded ethernet cables. Going to cat6 or cat7 is a mistake. You do not need them for audio, and you raise the bandwidth, raising the amount of EMI that can go through the cable.
Shielding and metal connectors  (no plastic) are the 2 main characteristics for ethernet audio. Some € on ebay. 

For Antoine, you do not always need to know exactly what is happening "inside" to try to solve a problem. As I say sometimes, you do not need to be God to cure people.


Nevertheless, I have a fear.

If it is the internal Switching Power Supply of Devialet that is the source of EMI that shut down the ethernet, and Switching Power Supplies are a HUGE source of EMI (check with Google), then I have no solution to propose. Better shielding should be required inside Devialet. And that is one of the reasons why High End audio gears have often an external power supply. 

If optical bridge does not solve the issue, well, I won't get chocolates. 

Kind regards.