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Audiophile Network Switches for Streaming ... really ?

tuga said:
I wonder if this could be relevant:

Staying Well Grounded
Hank Zumbahlen (Analog Devices)

https://www.analog.com/media/en/ana...6/number-2/articles/staying_well_grounded.pdf
Click to expand...

I used to work with the cutting edge sample and hold devices and ADCs back in the late 80s and early 90s in the lab, even before we had sampling ADCs. They'd be a few thousand of dollars each - no kidding for the fastest stuff, AD and Datel. I built pulsed lasers that were at least a factor or 10 thousand or so faster that the best devices (a few ns) bitd. The electronics were always limiting. You can't just shove this stuff in cheap, plastic enclosures without giving serious concern to the design and layout of the circuit, ground planes etc at those frequencies.
 
tuga said:
Another one piece grounding:

Grounding Data Converters and Solving the Mystery of "AGND" and "DGND"
Walt Kester, James Bryant, Mike Byrne (Analog Devices)

https://www.analog.com/media/en/training-seminars/tutorials/MT-031.pdf
Click to expand...
One would assume that the DAC has been earthed correctly, what are you paying that cash for. If it hasn't then we are back to sq's point that the audibility of the noise is poor design and not the network switch.

I'm not quite sure why you have posted the link tbh, just indicates good ground design practice for mixed signal ICs. If you don't do it that-a-way then be prepared for poor performance...

Ah, so is it possible to conclude that network switches only impact poorly designed DACs?

Damn, that needs a smiley or I'll be taken the wrong way. :)
 
Sue Pertwee-Tyr said:
Well, I wouldn't rule out some form of intermodulation. Can you?
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Agreed and as I have mentioned before, my suspicion is that the (above audio band) noise causes IMD in the analogue stages of the DAC and if so one should look for IM distortion rather than noise in the ouputs. I am pretty sure I have read somewhere that even very low levels of this distortion are easily audible but less easily measured due to their low levels. It goes without saying that those who say they have no noise because they cannot hear it at full volume without any music playing are missing the point that the noise itself is above the audio band and the distortion only happens when music is playing.
 
Fourlegs said:
Agreed and as I have mentioned before, my suspicion is that the (above audio band) noise causes IMD in the analogue stages of the DAC and if so one should look for IM distortion rather than noise in the ouputs. I am pretty sure I have read somewhere that even very low levels of this distortion are easily audible but less easily measured due to their low levels. It goes without saying that those who say they have no noise because they cannot hear it at full volume without any music playing are missing the point that the noise itself is above the audio band and the distortion only happens when music is playing.
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The ear is a measuring thing with physical properties that are well understood, a scientific instrument can measure further, wider and deeper than the ear, but still there is no measured proof of the low level of distortion that only an ear can hear. Ears are well understood things, what is less well understood is the influence of the brain on hearing and how external cues shape the sound we hear.

I suffer from something similar, something that I can't control even though I have noticed it for years. If I listen to music with my eyes closed the sound stage moves to the left, but if I open my eyes and look straight ahead, centre of the speakers the sound stage re-centres. I consciously can not control it, my brain directly influences the sound, affects my hearing.

What frequencies do you think the IMPs are being generated from? Surely someone must have measured those, else we are at the belief stage? :)
 
Here you go again folks - something to see you through the dark winter nights ;)
Already posted on pge 22 of this thread ... quite amazed this is still raging on unabated :confused:

Some actually relevant data :D

Noise%2BCompare%2B-%2BNo%2BEthernet%2B-%2B60Hz%2Bcircled.png


http://archimago.blogspot.com/2016/11/measurements-on-value-for-ethernet.html#more

Feast on that ...........
 
Maybe one day someone will show a measurement for the output stage of a dac with this magic noise on it and it modulating back down multiple times into the audible band.

Seeing as there are plenty of tests showing no real noise on the output of even cheap dacs out past 300khz, and plenty of the same dacs with better than -130db for a 32tone IMD.

I'm not going to lose any sleep over it being the root of some compounded evil.

It maybe worth worrying about in a world where every device amplifies dc to light and no circuit has any psrr and low pass filters never existed. Back in the real world though....
 
sq225917 said:
I'm not going to lose any sleep over it being the root of some compounded evil.
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Neither am I losing sleep over it. I am happy that I am fine tuning my system to sound its best based on selecting components and device connection based on what sounds best.

In the meantime I am settling down this evening to rerunning a selection procedure to decide which server and and player software sounds best in my system. I thought I would revisit Roon Server / Roon Player vs Roon Server / Squeezelite Player. The former sounds all closed in where the latter seems to have its percussion and top end slightly exaggerated. Having now changed to Squeeze server (LMS) and Squeezelite player everything sounds so much better.

Obviously I am only kidding myself as to the imagined differences because they are all bit perfect digital streams with all processing features disabled but welcome to my world where I hear differences in sound due to switches and differences in sound due to the different Server and Player apps.
 
tuga said:
According to Jussi Laako the relevant range is above 20KHz and up to 1MHz.
Not much of a relevant feast...
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Does Jussi say how that signal gets into the audio band, noting that filters after DACs remove those artefacts? You'll be telling me that people don't know how to design filters next :)

Point me at the precise discussion text where he provides proof of his claim.

It is great to say something without saying how
 
gavreid said:
I'm not getting into 'audiophile' switches but I do note that even the relatively cheap metal cased, 4 way, unmanaged switches have a mechanism to earth the casing...
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But clearly you are getting into letting theory get in the way of practice. Earthing or not, that cheap metal switch will have a clearly audible impact on most systems, not only those with a crappily designed streamer or DAC...
 
chiily said:
One would assume that the DAC has been earthed correctly, what are you paying that cash for. If it hasn't then we are back to sq's point that the audibility of the noise is poor design and not the network switch.

I'm not quite sure why you have posted the link tbh, just indicates good ground design practice for mixed signal ICs. If you don't do it that-a-way then be prepared for poor performance...

Ah, so is it possible to conclude that network switches only impact poorly designed DACs?

Damn, that needs a smiley or I'll be taken the wrong way. :)
Click to expand...

With all (and I do mean all) due respect, no.

This suggests that a switch makes a difference only either (a) where the user has an overactive imagination and/or (b) where the streamer and/or DAC they use is poorly designed. You really do need to hear the difference a switch makes to even a well-designed DAC before you tie yourself to that mast.

The noise is not audible in the sense most people would intepret that. We're not talking hisses and pops and stuff. You only "hear" it when you've heard your system with and without it.

Think high quality passive preamp like Music First Audio Baby Ref. I thought I had a had a great pre, very transparent, didn't get in the way of the music. When I replaced it with a Baby Ref, the difference was jaw-dropping. With the former preamp, the system sounded great; no "distortion", just great music; but with the Baby Ref, drums were visceral, double bass plucks in the room etc etc. A Baby Ref passive pre can't add anything to the the music; all it can do is to show what getting out of the way sounds like - what removing distortion sounds like. It's incredible.

I'm not seeking to equate the scale of impact of a switch (installed just before the streamer not just anywhere) with that of something like an MFA Baby Ref of course; I merely seek to point out how the absence of something you didn't previously realise was there - because you can't hear it explicitly - can make a serious difference. I just wish more people would risk exposing themselves to the experience so they could speak from both theoretical and practical bases.
 
sq225917 said:
Maybe one day someone will show a measurement for the output stage of a dac with this magic noise on it and it modulating back down multiple times into the audible band.

Seeing as there are plenty of tests showing no real noise on the output of even cheap dacs out past 300khz, and plenty of the same dacs with better than -130db for a 32tone IMD.

I'm not going to lose any sleep over it being the root of some compounded evil.

It maybe worth worrying about in a world where every device amplifies dc to light and no circuit has any psrr and low pass filters never existed. Back in the real world though....
Click to expand...
Maybe one day someone will risk using their unreliable ears. And then we can work out, together, what we need to measure to explain how we're hearing what we're hearing.
 
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