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Melco S100 Ethernet Switch Measurements


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36 minutes ago, plissken said:

I heard that having your wall framing made of metal stud makes your sound system better vs wood framing...

The worst is glass. Including huge TV. And not to forget bend radius of your cables. Fiber of cause most sensitive. But it can be fixed with dipping into hot water. 

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1 minute ago, R1200CL said:

Phase noice, jitter, and what ever make sense to measure. I think you know. (Much better than me). 

 

Measure jitter all you want. These are not real time systems. Jitter only appears on data transfer. The higher the speed obtainable the smaller the window of transfer.

 

You can't have jitter when the line isn't doing anything.

 

If you take 10GB and you can realize it's 1250MB/s you can transfer, on an appropriately engineered system, a CD in about .6 of a second. 

 

Even if you have a system that can only cache 30-60 seconds of audio your time on the wire at 10GB is going to scale just the same.

 

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1 minute ago, plissken said:

 

Measure jitter all you want. These are not real time systems. Jitter only appears on data transfer. The higher the speed obtainable the smaller the window of transfer.

 

You can't have jitter when the line isn't doing anything.

 

If you take 10GB and you can realize it's 1250MB/s you can transfer, on an appropriately engineered system, a CD in about .6 of a second. 

 

Even if you have a system that can only cache 30-60 seconds of audio your time on the wire at 10GB is going to scale just the same.

 

So in what way should measurements of a switch be done ? 
What parameters matters ?

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2 hours ago, R1200CL said:

So in what way should measurements of a switch be done ? 
What parameters matters ?

 

You are operating under the assumption that switches change your realtime sound quality. That is if you are listening to a 10 minute track it's for the duration.

 

This is simply not the way it works. I've been more than fair in offering cash to anyone that can demonstrate this.

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3 minutes ago, R1200CL said:

So how does it work ?

 

If you've been keeping up with the thread both Miska and Myself have been explaining.

 

802.3az is something you should read up on for starts. Ethernet operates at full wirespeed. Copy over a 75MB 16/44.1 audio track and it will go at full speed. On GBe it will take a split second. Literally.

 

On well optimized playback systems it will do the same and then let the Ethernet connect sit idle and even bring down the power and also power down certain parts of the Ethernet PHY.

 

The point in time that you are listening was most likely delivered seconds before if not minutes before.

 

Again what does the switch have to do with audio after it's been copied over? You don't even need the switch.

 

 

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9 hours ago, mecani said:

I can be a bit heavy but has anyone here heard the melco s100?


If you search the other forums, there are plenty of people that have reported on listening impressions, as well as the buffalo switch which is essentially the same as the melco. You’re not going to find listening impressions in this objective forum.

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3 hours ago, R1200CL said:

Instead of me arguing, can you explain why a switch like the etherRegen won’t matter based on Alex and John’s explanations here:

 

 

 

I'd rather use their own White Paper:

Q. What about systems in which a very large buffer holds a whole song or whole album?

 

A. A very large buffer where the input completely shuts down while all music is playing can eliminate the phase-noise overlay of upstream sources. However, leakage current is still there. As long as the cable is still plugged in leakage current is still flowing through the cable towards the DAC. So just not sending any packets does not make any differencethe cable has to be unplugged to stop it. Even if there are zero packets from the control system during playback you still have leakage coming from the switch and other upstream network components.

 

     1. They have yet, after years now, failed to show any measurements to this effect on a DAC output.

     2. Use wireless (I'm running two TP-Link Omada 1350 in VHT80 with 802.11K/R/V for seamless roaming) $112.

         I routinely get 38MB/s.

     3. Use fiber and while your at it use 10GBe if you can. My 10GBe setup cost 1/3 to 1/10th of 'Audiophile Switch'

         options ($210 for Cisco 2360, Solar Flare and Dell NIC's, and FS.COM SFP+ and fiber patch).

 

So we can effectively discount with item 1, and even if we don't I have two solutions at $112 and $210 that are better by their own admission.

 

 

Q. What about fiber-optic interfaces? Don’t these block everything?

 

A. In the case of a pure optical input (zero metal connection), this does block leakage current, but it does not block phase-noise affects. The optical connection is like any other isolator: jitter on the input is transmitted down the fiber and shows up at the receiver. If the receiver reclocks the data with a local clock, you still have the effects of the ground plane-noise from the data causing threshold changes on the reclocking circuit, thus overlaying on top of the local clock

 

         1. By omission it is left out that this only happens on Data Transfer.

         2. 10GBe and higher have much more stringent Jitter requirements. Most likely beyond what  

             boutique audio switch manufacturers can produce. I would say that a $20 multi-mode

             10GBe LC SFP+ tranceiver has tighter tolerances than any 'audio-phile switch'. @jabbr

             comment on that one.

 

 

 

 

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@plissken

My understanding is you pull out the cable in order to eliminate leakage current, so with optical cables there isn’t a need for this. 
I suppose if a buffer is to be used in order to block phase noise (jitter), this buffer must be located after last network interface, so it can’t be inside a switch.  Maybe it can be inside the opticalRendu (I know there is one, but not sure how big, or if it does anything to reduce jitter). 
 

Where is your buffer located and what size does it have ?

 

@JohnSwenson

Would a dual design of buffers (somewhere) where the design is made a way altering between the buffers be a solution to almost totally eliminate phase noise / jitter ?


And if so yes in theory it may not be so easily done in practice. 


Or maybe the opticalRendu already eliminating phase noise the way described in white paper ?

 

I like the idea of optical 10Gbs Ethernet switches. As they most likely have higher jitter requirements. Should I expect your etherRegen or opticalRendu (and opticalModule) to work with and benefit from such switches ? I think not. 

 

I suppose the only way this can work is if those 10GB switches also do 1 GB, and I don’t think they do. So it’s up to the SFP Small form-factor pluggable transceiver maybe ?

@jabbr Maybe you can explain what’s possible with 10GB into 1GB. 

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7 minutes ago, R1200CL said:

@plissken

My understanding is you pull out the cable in order to eliminate leakage current, so with optical cables there isn’t a need for this. 
I suppose if a buffer is to be used in order to block phase noise (jitter), this buffer must be located after last network interface, so it can’t be inside a switch.  Maybe it can be inside the opticalRendu (I know there is one, but not sure how big, or if it does anything to reduce jitter). 
 

Where is your buffer located and what size does it have ?

 

1. Switches do have buffers and you can manipulate these with various commands to affect priority que.

2. A buffers sole job is to establish a clock domain boundary for systems that have different timings.

3. My buffer is 1GB of RAM on my JRiver based system. This is why I always point out 'correctly designed/engineered systems'.

4. Even a buffer of a single MB is enough. But what that does is keep the receiver PHY in play longer over the duration. I prefer as much wire speed as possible and buffer up front.

7 minutes ago, R1200CL said:

I suppose the only way this can work is if those 10GB switches also do 1 GB, and I don’t think they do. So it’s up to the SFP Small form-factor pluggable transceiver maybe ?

@jabbr Maybe you can explain what’s possible with 10GB into 1GB. 

 

Switches that have SFP+ (or SFP10) can do 1 GB. You just pop in the compatible 1GB modules on both ends. SFP* modules are fixed rate and have to match on both ends.

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Here’s the thing. Take a hi-res system with a server like an Extreme or an Innuos Statement and set it up for local (internal storage) and remote streaming (via Internet or networked disc).  Both servers play files from internal RAM. Play the same recording and the SQ will generally favour the locally stored file. Add a Melco S100 to the network and the remote streaming improves, but generally, so too does the local streaming.  Add a high quality power supply to the Melco and the SQ of remote streaming improves, but so too the SQ of the locally stored files.  Disconnect the network entirely and the SQ of the locally stored files improves. So it would seem that the improvements have more to do with noise and how it affects processes within the DAC.

 

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18 minutes ago, jabbr said:

10Gbe Ethernet has very low phase noise/jitter *as specified* and moreover jitter is *not allowed* to travel from one hop to the next. This is written into the compliance testing specifications. I’ve posted on this exhaustively.

And is not affected by choice of SFP ? (No problem with 1GB versions on 10GB switches). 

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15 minutes ago, Blackmorec said:

Here’s the thing. Take a hi-res system with a server like an Extreme or an Innuos Statement and set it up for local (internal storage) and remote streaming (via Internet of Networked disc).  Both servers play files from internal RAM. Play the same recording and the SQ will generally favour the locally stored file. Add a Melco S100 to the network and the remote streaming improves, but generally, so too does the local streaming.  Add a high quality power supply to the Melco and the SQ of remote streaming improves, but so too the SQ of the locally stored files.  Disconnect the network entirely and the SQ of the locally stored files improves. So it would seem that the improvements have more to do with noise and how it affects processes within the DAC.

 

 

Here is a video I shot with an Audiophile Switch. It's short and to the point. I would love to see you tell when the switch is in and out of loop.

 

 

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On 9/17/2020 at 6:06 PM, plissken said:

Here is a video I shot with an Audiophile Switch. It's short and to the point. I would love to see you tell when the switch is in and out of loop.

 


Wouldn't pulling the USB cable make same result? (You will have the same buffer there). 

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