Noise measurement ethernet port
Contents
Isolation Spectrum analyzer
How well does a switch isolate between ports? After all, if a device emits a lot of noise, it can leak noise to other ports.
For this test, we inject white noise into the switch and see how well the switch manages to keep it away from other ports.
Again, we see big differences between the various models. Each model filters differently. The new Dlink 108 V4 filters much better than the old 108 V3. The Dlink 1100 is clearly based on the older 108. The Dlink 108V4 scores very well in this test.
The Netgear 108 and 108E differ from each other. The 108T is similar to the 108E. Both filter better than the regular 108. Netgear scores very well here with the 108E and 108T.
The Zyxel 1200-08 does not seem to filter very well. The 2200 does much better, we know from other / older surveys.
What we clearly see with all switches is that it is crucial to ground things properly: that significantly reduces the noise floor. We have also tested and heard this before: focus improves and there is more calmness in the soundstage and presentation.
Noise from LAN port – Picoscope
We also measured the noise from the lan port. This is done through a so-called CDN – Coupling / Decoupling Network. We capture the noise from the port and send it through a splitter for differential and common mode noise.
What is noticeable is that the Netgear measures the quietest. And then the GS108E version. The Dlink 108 V4 is close to that. That also comes from the previous measurement where we measure port isolation.
The power supply – as you can see – is crucial to the noise level. Both linear power supplies and filtered versions perform significantly better than standard adapters. We see this later also in the jitter measurement.
100 Mbit?
However, what is also noticeable is that the 100 Mbit ports show much more spikes / noise. Now this could be due to two things: the noise is just higher, or we are looking at data. Now it is true that the absolute noise floor is lower. But so there are also a lot of spikes. We are looking into this further.
Just joined the club.. I thought this was all BS….
As initial test just bought the 89,- Euro IFI audio Lan silencer. Assume not much more then a kind of opto decoupler (galvanic separation) that gets rid of the cable (Cat 6) LAN noise collected on the way to my streamer.
It does however a lot more then expected. The bass is punchier, deeper, well rounded, some harshness on the edges on the highs sound more rounded, less ‘s’ in the vocals, overall there is more clarity, better mirco details, different tonality in the vocals, more room in the mids, improved 3d soundstage, decay or reverb of instruments more precise. Great upgrade for the money…
Actually need to get used to this new ‘sound’ it takes some life (distortion) out of music as well, it sounds great but also too analytical for my ears.
Still think you better spend 300 Euro on a set of decent speaker cables first then on a router, but if you got all things right already, Upgrading the Lan connection may unexpectedly do more then you think.
Tested the IFI silencer on:
-Wiim Ultra
-Eversolo DMP-A6 gen1 (upgraded with linear power supply)
On the stereo set using the Wiim ultra the experience is similar as upgrading the Eversolo with a linear power supply.
Setup 1:
Wiim Ultra – usb out fixed setting 32bit 192Khz – to a Fio K11 R2R dac (Brz hifi linear power supply) which plays to a Cayin EL34 tube amp – Triangle Comete 40 speakers.
Setup 2:
On the set using the DMP-A6 not a real difference noticed, this one is standard behind a Netgear switch (with original switching power supply). The DMP-A6 plays via Hdmi cable – Yamaha RX-1060 receiver – via pre out to Schiit tube pre amp – Wilsenton R8 El34 tubes. This Hybrid setup plays to 12 speakers (Piega, Dali, Sound Artist) For music usually use 7 stereo setting, For gaming and movies Dolby Atmos, DTS-X depends on the source.
I am a believer in good linear power supplies, will check what happens 3 swtiches to go. Also will upgrade to Cat 8 cables on some positions.
We know now for sure it is audible and needs some money…
Thank you very much for testing !!
Hi guys!
Thank you for your work and sharing it.
Could you please clarify which Lineair power supply from AliExpress did you use?
Thank you.
Greatly appreciate it
BRZHiFi… 5V
Sir,
Thank you!
Sean
You are very welcome
Sirs,
Trying to follow your D-Link advice but cannot distinguish DGS-108 Version 3 from 4.
D-link does not assist and email to D-Link not returned.
Mine also says on Box: 8 port Gigabit desktop switch. One light on each port.
On bottom says: H/W Ver.:E1.
Very much enjoy your testing!
Best!
Sean
Hi Sean. Version E1 is version 4. Version 3 is indicated as C6.
I’ve used an iFi SupaNova (included filter) power cable in the network box + an IEC C14 to Schucko female before the distributor for switches. This way all the equipment (router, switches, media converters) benefit from the power filtering.
For grounding the switches (better said, EMI/RFI draining) one can also use the ToughCable Connector Ground from Ubiquiti which can be plugged in one free Ethernet port. I prefer padding the interior of metal casing of the switch with copper adhesive foil and insert a drain copper wire or screw and then plug it (with a regular banana connector) to the special jack in the iFi / SilentPower AC iPurifier (that can be plugged in a free Schucko outlet).
a question: what kind of filters did you use?
It is a filter between the power supply and the switch.
the question was more related to brand and model
hi Jaap. Can you share information about the filter?
Can you elaborate bit more on this?
“What we clearly see with all switches is that it is crucial to ground things properly: that significantly reduces the noise floor. “
What else do you need to know? Grounding the switch – for example the casing – lowers noise.
There’s no ground connectors on normal switches so I o wondering how you go about this. Entreq for example have ground RJ45 connectors connected to ground boxes. But as I understand you you mean adding a cable to the chassis somewhere and connect to mains ground or?
The D-Link switch has a grounding screw on the case, for instance. Connect a wire from the case, with the D-Link from the screw, to the earth connection of an earthed plug and put that plug into an earthed socket. We tested it like that a few times, and it is clearly audible.
Only do so when you know what you are doing.