Ethernet Switch and Cables Mania

Exaktly (pun) what, though?

Genuinely, what DSM model are you using and also what speakers in both systems?

I tried, but but because of the lack of any configuration control on my NAS of DSCP and mixed flows on the same port, … I couldn’t configure it in any meaningful way.

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Indeed , however the GLC-SX-MM is obsolete and very long in the tooth now… you ideally should be using GLC-SX-MMD.
The D refers to ‘digital optical monitoring’ and that allows current standardized way of reporting optical performance to the switch so as to remove the uncertainty with optical performance.(power/length/attenuation etc)

Also with fibre, do try and keep away from sources of high volume, fibres are extremely microscopic, introducing jitter related sidebands into the frame flows that will couple as a degree of digital noise. I have undertaken some interesting observations professionally here as well.

The Roman uses 4 random car stereo speakers that he found in Steptoe and Sons junk shop when he was a prop buyer at the Beeb in the 60s - but he can’t hear any differences between them.

He is too engrossed in the music.

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In that case, adding a second Switch, to which we only attach the server (roon) and the streamer (NDxxx), could do the trick.

I probably have the same problem. I use Roon Rock which runs on top of a Linux kernel. But not sure I can set the DSCP values for the outgoing traffic.

If you use a MacOS to run Roon Server you probably could do that.

Ahh but if you have a server only doing a single function with a single primary flow, then you can set the DSP at ingress on the switch port. You won’t need a separate switch for that.

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Did you mean to say that fibres are extremely microphonic?

I would like to see your system in systems pics 2020 . The doubts would vanish.

Prepare for audiphile optical cables an inch thick, due to the vibration absorbing layer, and maybe heavy due to the massy outer sleeve. Though actually I guess something like that it might be a realistic approach, unless the receiver can reject the digital noise/jitter.

Surely, if you send all this digital data to a receiving buffer, it can re-clock itself before streaming it to your hifi system ?

Interesting, I stumbled across an article a couple of years ago describing a study (I think it was from a University in Poland) where fibre laid along a railway line was found to modulate the vibrations caused by passing trains. A rather different scenario, but still, perhaps something for the ‘bits are bits’ brigade to think about.

Regarding the SFP specs, mine are regular MM, but seem to work perfectly well. Would MMDs work any differently in an unconfigured switch? I could easily swap them out, but perhaps, if it ain’t bust, don’t fix it. I notice the SFPs that @Darkebear has been trying are MMD, but not Cisco branded.

How’s that PoE switch working out?

Hi Simon
If I end up with a 2960 C Series non-PoE then a 3560 PoE switch into a 2960 PD - would I be able to deploy ether-channel transmission across all three of those switches, e.g. using 2 cables between each pair of switches?

With just one PoE and one nonPoE cable between the last two switches?

Oh yes, I have some examples in this regard, including security and surveillance as well.

As I always I say, bits are bits, but in a serial stream of bits (like in Ethernet, usb, SPDIF etc) it’s meaningless without the dimension of time/propagation … and this is often the bit that modulates.

I don’t see why not.

I had assumed that the “bits” included a few “bits” that defined the timing at which all the other “bits” had to present themselves.

When you used it, did you use 3 switches and 4 cables?

I have gone wireless. It really is so great on the new streamers. I have just rigged back up my 2xCisco PD switches and can detect no differences in sound. So I’m sticking with wireless now. Can stream all the Naim videos from YouTube with no drop outs too. No wires, no SMPS, no clutter and no neurosis.

Happy Listening!

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So you’e saying that (in your wireless vs wired network, into your streamer, your system, your room and your ears) no cable sounds the same as whatever cables you had settled on (sorry, I lost track of which), and no switch sounds the same as two switches? H

Have you Blind Tune-Demmed?

Just wait till the radio waves burn in!

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No. I have never been on a blind date.

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