Nordost Heimdall 2 Ethernet Cable Review

[jolon]

6 minutes ago, jolon said:

Are you referring to the dBfs comment above?

 

You can see the peak-to-peak measurement in the screenshots. It's the RCA output of the Linn Sneaky MDS so I presume it is probably max ~2V.

 

It's worth pointing out that I don't believe the Sneaky has magnetics on the Ethernet connector, and neither does my Yamaha R-N602. The Acoustic Revive is basically magnetics in a connector, so by simply having magnetics reduces a lot of the noise.

 

The Sneaky was originally released in 2008 and the architecture hasn't changed since then. So it is one of the earliest network streamers and I'm sure a lot has been learned since then (including myself!)

 

I've largely switched to fiber now with a media converter before the network streamer and it sounds the best I've heard it so far. It's made me think it would be nice if manufacturers used an SFP connector. By default it could be an Ethernet SFP, but we could have the option of using fiber without requiring an external box and power supply.

[plissken]

I'm seeing 3.68mil volt. As in thousandths?

[plissken]

28 minutes ago, jolon said:

 

It's worth pointing out that I don't believe the Sneaky has magnetics on the Ethernet connector, and neither does my Yamaha R-N602. The Acoustic Revive is basically magnetics in a connector, so by simply having magnetics reduces a lot of the noise.

 

The Sneaky was originally released in 2008 and the architecture hasn't changed since then. So it is one of the earliest network streamers and I'm sure a lot has been learned since then (including myself!)

 

I've largely switched to fiber now with a media converter before the network streamer and it sounds the best I've heard it so far. It's made me think it would be nice if manufacturers used an SFP connector. By default it could be an Ethernet SFP, but we could have the option of using fiber without requiring an external box and power supply.

 

What year did you do the measurements? I didn't see any indication that this may have been more an issue of how the PHY was implemented rather than the cable connecting it.

 

So in either the Generic or the AQ we are simply seeing some modulation due to the LCR characteristics of the cable. Given the milvolt output I don't see how it's audible with either. 

 

I like WiFi. 

[jolon]

37 minutes ago, plissken said:

I'm seeing 3.68mil volt. As in thousandths?

Yes

[jolon]

32 minutes ago, plissken said:

 

What year did you do the measurements? I didn't see any indication that this may have been more an issue of how the PHY was implemented rather than the cable connecting it.

 

So in either the Generic or the AQ we are simply seeing some modulation due to the LCR characteristics of the cable. Given the milvolt output I don't see how it's audible with either. 

 

I like WiFi. 

I did the test mid-2015. The Sneaky I had (now sold) was purchased in 2014, however I don't believe the Sneaky internal components changed much since its introduction (~2008).

[plissken]

19 hours ago, jolon said:

Yes

 

3 millivolt isn't audible. 3 thousandths is just nothing.

[jolon]

4 hours ago, plissken said:

 

3 millivolt isn't audible. 3 thousandths is just nothing.

 

Let's say it is 1 thousandth of the maximum output. You can represent that resolution with 10 bits. Are you happy with 10 bit audio?

 

(2^10 = 1024)

[plissken]

You are talking 8.46e ^-7  watts of energy at 8 ohms. 

 

What was your termination value of the scope?

[jolon]

23 minutes ago, plissken said:

You are talking 8.46e ^-7  watts of energy at 8 ohms. 

 

What was your termination value of the scope?

Watts at the speaker depends on volume. Not sure how you got that value. I was measuring the RCA outputs.

 

Input impedance of scope would be quite high, I would have to check.

[plissken]

What would 0.00368 worst case or 0.00212 best case peak would end up being under amplification?

 

Your own measurements really aren't about Ethernet cabling, IMO, but about the fact the Sneaky DS doesn't adhere to best practices as we see the result with the isolator in place providing that functionality. 

 

The measurements are laudable for the attempt but I think they mislead people that aren't going to critically think about what you measured and don't know that the Sneaky DS is a sub-optimal implementation as that piece of information is missing.

 

There was a round of RasPi's that had the magnetics package in the RJE missing and it was clearly audible no matter the RJE cable used.