Network Switches

You will not be missed by me, at least, because frankly, you are technically ignorant. You are the guy trusted to put in network equipment and run cables.  You are not the guy trusted to design the audio equipment, nor the guy trusted to write the protocols for the audio, or anything that gets into anything technical in depth.

1. I never ever said I would not have my perceptions put to the test. I call out false claims when I see them, but have to admit to potential sources when they exist.
   
2. With almost no exception is anyone claiming here that the switch is changing the "fidelity" of the digital audio stream. You are saying that.
   
3. I clearly, in terms you should be able to understand, communicated how changing packet rate could induce a change in the noise signature in the end-point equipment. Not the data being received, but an analog noise signature via pumping of the end equipment power supply rails. Perhaps you do not understand what I am communicating because you do not have the knowledge to understand it?
   
4. It has clearly been communicated here to you as well, how, noise can be injected via ethernet connections could influence end equipment results. Not the digital transmission which is fairly noise immune, but injected noise into analog sections. Ethernet transformers are actually fairly wide bandwidth offering a path to noise injection.

You say people don't want to learn, but other than slinging insults, you have not communicated one iota of information, nor have you even refuted the actual arguments presented w.r.t. analog noise injection, potential for noise pumping, etc. You just keep repeating the same things over and over again that no one seems to be even disputing.
Bye Mike.

mike201913 posts10-31-2019 11:32am

I must say that I find it amusing that one of those claiming that cables and switches can enhance digitised audio can ask for 'evidence' when refusing time after time to have their perceptions put to a proper test. very droll

Experience and qualifications ? I am the guy with years of experience trusted by recording studios and TV studios.... and you are the guy who thinks that a switch can change the fidelity of a digitised audio stream passing through it........... hmmm

Natural selection will eventually put these bogus switch and cable manufacturers out of business by removing their patsies as, presumably, it is the same people who believe the cable and switch manufacturers rather than believe experts and facts who will also believe, for example, the ads for Miracle Mineral Solution rather than believe the FDA.

They will carry on drinking very expensive bleach to their last breath, while telling the medical experts that they don't know what they are talking about.

I give up. some people just do not want to learn.

I have just found a forum where pseudo science and ridiculous claims are forbidden

I won't be here to see your reply but thanks for a (reasonably) civilised discussion :)

(and I am still looking for anybody to explain how a cable or a switch can adjust or change or enhance a digitised audio file passing through it. Just take a while to think about the impossibility of that claim)

thanks

see y'all

While I am under no illusion that data transmission in USB, Ethernet is at all being affected in a home network given the astonishingly low bit error rates typical in a home and jitter is simply not an issue at all in any modern USB DAC and not at all in Ethernet. But, I cannot rule out, especially given I am also under no illusion that all audio products have good analog design, that noise injection through the power supply could make a difference in some circumstances. In a well designed products it should not/will not, but I cannot assume that is ever the case. The type of power supply noise generated would not be negated by high end cables. They could even make it worse by providing a lower impedance power path. Then again, some like the "airy-ness" that noise provides.

allane37 posts10-30-2019 8:32amIt seems that if there is an audio performance benefit from network hardware, that maybe it’s because of “electrical noise” as opposed to “data bits”?  Power supplies seem to make a difference with both analog and digital designs, and most of these “audio grade” switches focus on electrical isolation.  This would explain why fiber and optical connections can benefit some systems.

Maybe instead of counting bits we should evaluate the way power is implemented?

The bits are there, but the power they are riding on could be better?

I think this also applies to USB from a computer to a DAC, which is why I’ve been testing/listening to some USB interfaces for my Apple Mac.  https://forum.audiogon.com/discussions/apple-music-mac

I am new here and I don't find this argument/post very inviting. As opposed to inviting discussion and trying to get to the bottom of a topic that is obviously interesting to the community, it appears to be attempt to shut down discussion and force a particular view/outcome. This seems more akin to Facebook groups. I hoped to avoid that here.

 steakster858 posts10-30-2019 1:55pmIt appears that some posters here don’t know the difference between obtaining optimal sound vs any sound. Perhaps, their systems aren’t resolving enough to demonstrate improvements. Unfortunately, these posters are polluting other member’s threads with distracting noise.

This is an interesting take, going beyond just power supply noise injection, and considering signal injection. I will throw out some thoughts at you w.r.t. that. Please take them as just that, arguments, not attacks on the precept.

• Almost exclusively, the claims are that Cat-6/7/etc. "sounds better". While that claim may not be accurate, Cat 6/7 will allow much higher signal edge speeds, which would lead to more noise injection by your proposed method.
• Even for these custom designs, they would use off the shelf ethernet drivers to ensure compatibility and they are forced into a specific impedance. I would expect most use off the shelf ethernet transformers as well. You could edge shape with some capacitance to decrease capacitive noise transfer, but then you are likely to create more end-point jitter  (and see first argument).
• Outside of the high frequencies, which can get in, but are also the most likely to be filtered at some point, the subharmonics which could be in the audio band or modulated down are going to be mainly a function of the data itself.

Just some more thoughts to ponder on to add to your valuable post.

 s

almarg9,123 posts10-29-2019 9:14amAs someone having extensive experience in digital (and analog) design, although not for audio, it is very conceivable to me that a network switch can make a difference sonically. Not because it affects the accuracy with which 1s and 0s are received; not because it affects the timing with which those bits are received; and probably not because of most of the reasons that are likely to be offered in the marketing literature of makers of audiophile-oriented switches.

The likely reason relates to differences in waveform characteristics such as signal risetimes and falltimes (i.e., the amount of time it takes for the signal to transition from its lower voltage state to its higher voltage state and vice versa); differences in noise that may be riding on the signal; and differences in distortion of the waveform that may be present. In other words, things that affect the spectral composition of the waveform.

I think there are things that can be dismissed out of hand in audio, but many that can't, this would be one of them.
I have not read about anyone doing specific matching on ICs / Transformers, but I have to expect the variance is as big in the cables, hence matching would probably be a pointless exercise. Generally at the receiving end of Ethernet, IMO, you are not getting too much ringing, more issues with softness of the edges due to bandwidth limiting with perhaps a bit of reflection, but usually buried in the signal. Of course, that is with typical 5/53e. Cat 7 would likely be prone to worse issues. This is based from work I have done in industrial ethernet applications.

W.R.T to below, most modern ethernet connections would be switched, and with the low data rate for audio coupled with 100mbps or 1gbps links, it would appear somewhat as regular timed bursts with some jitter on those bursts of course. In my heads calculations say those burst rates would be firmly in the audio frequency range.

That’s an interesting point. In typical circumstances, though, eight-bit bytes are being communicated in a matter of just a few nanoseconds, and most or all data bits are presumably toggling much of the time. So if, as I would presume, the edge speeds of those toggles, and the susceptibility of downstream circuitry to the injected “noise” corresponding to those edge speeds, as well as waveform distortion resulting from less than perfect impedance mismatches, as well as noise introduced by the network switch and its power supply, are all likely to vary significantly among different systems, cables, and network switches, it’s probably anyone’s guess as to which of the four contributors we have mentioned is likely to be most significant in a given application.

I am not sure how this is at all relevant to the discussion?

lalitk1,415 posts10-31-2019 8:19amAnd does any one of you use Vinyl as prime source of listening?

If you challenged me, I would probably go out on a limb and say that no, your technicians probably don’t know the underlying protocols for audio transmission over ethernet very well, but that is a moot point.

As I, Almarg, and others have stated so many times in this thread, which you seem to constantly ignore, is that it is not about digital data transmission, it is about noise injection into end equipment via the data lines and/or power supply lines when USB is being discussed.

However, it is not accurate to say that nothing done in the digital domain for audio can’t effect the analog outcome downstream. Packet rates for audio over ethernet are right in the middle of the audio bandwidth which could lead to power supply pumping in the downstream product due to varying power requirements in step with packet arrival. That pumping of the supply then coupling to the DAC section. At a switch level I could break big packets into small packets to change the packet arrival rate and the signature of that pumping.

mike201910 posts10-31-2019 9:30am @atdavid

Oh my goodness ! get into the 21st century. A network technician should know everything w.r.t. noise free analogue signal reconstruction.

mike201910 posts10-31-2019 9:57am @atdavid
When did I say I was a network technician ? That was many years ago. More recently I have designed and installed networks for the likes of TV and radio studios.
Besides which, if I discovered that one of my tecnicians did not know exactly how sound was encoded into a digital signal, transmitted and then decoded back to an audio signal, he or she will be looking for another job
How can a switch adjust the audio encoded in a digital signal passing through it ???? This is the sort of thing you really must try to learn about. IT CANT

While there are some who mistakenly believe, and others who mistakenly promote that bit timing matters in Ethernet/USB transmission, as has been noted above, frequently, any of the technical discussion in this thread has centered around analog noise injection and potential downstream effects. While I expect this to be limited in Ethernet due to inherent isolation, there is still the potential, and for USB, the potential for noise injection is very high and very real.


Now, do I personally believe that expensive audio ethernet cables makes any difference? No and in fact they could be worse. For USB, there is enough noise injection, that a cable could make a minor difference good or bad. On the other hand, with USB certainly, reducing power supply and AC ground noise could certainly have an impact as would isolation, and with Ethernet, if there is noise injection into the audio, then isolation will help.As Almarg has pointed out, the "claims" of some of these "audio switches" is questionable at best and probably misguided, however, that does not mean that other aspects of last few feet transmission could not have some impact on the usually flawed designed product being connected.


I also don’t go for these childish "your system/ears/etc. is not good enough to tell the difference crap", but I also don’t go for these calls to authority about my "awesome experience", when it is not awesome for the topic, and if you are going to do that within the framework of this discussion, I would not be using "software engineer", or "network technician" because that communicates no knowledge w.r.t. noise free analog signal reconstruction. Perhaps you could enlighten us on what the packet arrival rate would be for an digital audio signal over ethernet?

cakyol150 posts10-30-2019 11:57pmThere is no such thing as an audio network switch. They ALL work on digital mostly ethernet packets. It is LUDICROUS to think otherwise.

PS: I worked for Cisco for 17 years as a software technical lead and I am now at Broadcom as a principal software engineer, who makes the chips for these switches.

mike20195 posts10-31-2019 7:21am@audionoobie and jnorris2005 and @ cakyol

Save your breath guys, you are hitting your head against a brick wall. There are those who even believe that a different Ethernet cable or USB cable can ’improve the audio". I am afraid that no matter how much you try your best to explain to them the difference between analogue and digital, it is just fingers in ears and "la,la,la,la,la,la,la", " your equipment is not as expensive as mine", "your ears are not as good as mine" and then pages of things that can affect an audio signal

No mike2019, really, a "network technician" would not need to know everything about noise free analogue signal reconstruction. I am not sure how you can even make that claim. Tell me, in the course of your employment as "network technician", how many 10’s of products have you designed the circuitry for, laid out the PCB to reduce noise analog / digital interaction, worked out the packaging/ shielding? There is a big difference between the skill set for "network technician", and product/system development for low noise analog signal reconstruction.

I think you will find that most who question the basic premise of digital data transmission for audio transmission are not engineers.

mike20197 posts10-31-2019 9:30am @atdavid

"I would not be using "software engineer", or "network technician" because that communicates no knowledge w.r.t. noise free analog signal reconstruction"
Oh my goodness ! get into the 21st century. A network technician should know everything w.r.t. noise free analogue signal reconstruction.
The problem is that audio engineers have still to learn about digital transmission.

I personally on this thread have never used the word "sound-stage", and would not attribute a quality that is almost exclusively a function of speakers to noise injected into the analog section of a component. However, I also know that even audiophiles don’t know the proper words to describe what they are hearing often, and I know technically that a change is possible, so I am not ruling out it is occurring, and I do rule out many claims made in the audiophile world.

I find it rather hilarious though that you imply I have a "complete lack of knowledge of digital audio" and you are an expert when I would pretty much guarantee my comment about power supply pumping due to packet arrival rates never even occurred to you. Your statement w.r.t. noise injection shows a limited experience set. You may have a large experience set at a high level, but your comments show a limited knowledge set at the component implementation level.

These issue are not limited to home audio. Better quality industrial USB data acquisitions units have internal isolation. The ones that don’t are prone to measurement error and noise due to ground loops. In higher noise industrial environments, ethernet over fiber is not uncommon due to data loss issues with wired communication.

Other than "you are wrong", and that all bits are received, without issue and that bit timing is not critical, a fact that is actually not disputed by many in this community, I have yet to see evidence of your experience.

mike201912 posts10-31-2019 10:46am

@atdavid

" As I, Almarg, and others have stated so many times in this thread, which you seem to constantly ignore, is that it is not about digital data transmission, it is about noise injection into end equipment via the data lines and/or power supply lines when USB is being discussed."

I am not ignoring it, I am just pointing out that it is all about digital data transmission and how ridiculous it is to say that eliminating noise injection can, for example , "enhance the sound stage" and why is this only a problem in an "audiophile’s" home network and nowhere else in the world

I am sorry but you just continue to show your complete lack of knowledge regarding digital audio. Mine is very extensive

No, not better switching duties, but perhaps better noise isolation.

mitch22,069 posts10-31-2019 6:12pmso what I believe you are implying is that a separate switch will perform the switching duties better than my Orbi router.

My post was in reply to "there is no way the digital transmission can impact the audio" .... It was a thought exercise to show that yes, in fact, the method of digital transport can have unintended consequences that present themselves in the analog domain. I highly doubt something like this is implemented in any of the "audio" switches ... most of whose claims, other than reducing power supply and EMI, are questionable.

The pumping of the power supply rail with packet arrival is real and something I have seen in non-audio devices.

djones51667 posts10-31-2019 1:57pmFrom what I can gather from the links to the 3 switches mentioned in the OP the sotm switch is not a managed switch but a basic level 2 switch so I can’t see anyone being able to manage changing packet rates. I haven’t found as much on the other 2 but they look to be basic level 2 switches as well, perhaps someone has more info on them.

Ethernet is always galvanically isolated. The connection is through a transformer.

The only thing you are illustrating is your own lack of knowledge. I have developed quite a few products with Ethernet interfaces. Never once have I used a "network card". There are approximately 40-50 companies that make ICs with Ethernet interfaces. Easily that many that makes RJ45 jacks, ethernet transformers, etc., likely many that you have never hard of.

Your post illustrates a gross ignorance w.r.t. circuit design, whether digital or analog. That makes it pretty easy to pretty much ignore your posts as they are written from a position of ignorance, not education nor experience.

The rest of your post(s), just repeatedly illustrate you understand very little about what is being posted in this thread.

jnorris200576 posts11-04-2019 11:26am it communicates directly to the network card in the DAC and it’s buffers, where the signal is extracted from the ethernet packet and stored until the DAC requests it. These network cards are manufactured by a handful of chip companies and I guarantee that NONE of them are giving any attention to audio.

Actually 24 frames per second was a compromise, not perfect, but good enough in the early days when film was expensive. As "film" dies, and costs decrease, we will move towards higher frame rates to improve perception of motion. You know that "film" was flashed 3 times per second, which again was not ideal but an acceptable compromise.
Being able to see differences between 1080P and 4K is more a factor of corrected vision and screen distance, not age, at least to a somewhat advanced age unless there is specific macular degeneration.

Knowing everything about CODECs, digitizations and the limits of human hearing will not tell you anything about a specific DAC implementation and its susceptibility to EMI.

jason_k20176 posts11-04-2019 12:56am@nonoise

@jason_k2017, are you suggesting that what you're hearing is exactly as it was encoded? That your DAC is perfect?

The one thing I do know is that if you decode an encoded stream in a quality DAC with the the same codec with which it was encoded then it will be as near to perfect as anything else I can throw at my sound system. My turntable (which is no longer used) is not perfect, my CD player is not perfect, my DB receiver is not perfect. Nor are yours. None are

You should read up a little on codecs, digitzation and the capablilities and limitations of the human ear. There is a point at which nobody can detect an changes to audio. If you can't grasp that, think of your eyes instead and why film only needs only to be at 24 frames per second and why you have to be reasonably young to see any difference between 1080 and 4K TV

You appear to be attempting to communicate a level of technical astuteness with your post, but you appear to have missed the point completely.
Almost no one in this thread is questioning the digital communication of bits perfectly ... minus the standard data errors that do occur, albeit almost never with the confines of the last data transfer. With few exceptions in this thread, and we can discount them, has anyone suggested that the signal or data degrades. That you are using that argument suggests you have not read this thread or do not understand the contents of this thread.

What has been communicated, specifically by Almarg, is that the Ethernet connection, while transformer isolated, is still an entry point for EMI, both magnetically and capacitively.

jnorris200575 posts11-04-2019 12:01am

The fact is that this signal has passed through hundreds of routers, repeaters, data centers, and switches prior to arriving at your router. Are we to understand that all those networking devices have had no effect on the signal, thus allowing that signal to arrive at your digital doorstep in pristine condition? Are we to further understand that the only place deterioration of the signal can occur is within the final switch and hence that switch needs to be a magical audiophile switch.

Your whole argument sounds like the same pseudo-scientific verbiage used to describe other incredibly overpriced nonsense products that plague hi-end audio.  

No, only a one or two people who do not understand digital data transmission have suggested degradation of the digital signal. That vast majority of the posts have spoke to electrical noise being the most likely culprit.

I have also posited, because it is real and it happens, that data frame arrival, because it is periodic (and pseudo random) can also cause pumping of the power supply lines in the end equipment as the power supply load increases and decreases. That will be in the frequency range of audio and whether audible will be implementation dependent.

No, not new at all. 3 blade or 3x speed shutters were used with 16fps film early 20’s (or earlier). When the switch was made to 24fps, they dropped to 2 blades or 2x shutters, which was late 1920s.


I can’t remember when 3x shutters with 24fps became common, I want to say late 70’s, early 80’s, but even today, you would find 2x shutter regularly if the theater has not gone digital.

Yes, your ignorance is frustrating.


One of the hardest electrical engineering positions to recruit for is analog design, because unfortunately too many new engineering graduates are totally caught up in a perfect digital world and have no idea how the real world operates. They throw micro-controllers and processors down on a schematic and PCB, or heaven-forbid, a DC-DC with a multi-tap transformer, heck they probably followed the application note faithfully, but then are flummoxed when their creation does not work the way they expect it to.  Being a good analog engineer is harder and less forgiving than digital

I am going to guess you are on the "young" side. By your post, you would think you invented digital. Sorry to tell you, but while it is "new" to you and seemingly perfect, real engineers have been working with "digital" for decades and know there is a big difference between transmitting bits, and recreating a high resolution analog signal.


See here is the thing, when my battery is starting to run down in my BT headset, I know .... the sound starts to change. The bits are the same, but the sound coming out, you know that antiquated analog stuff .... ya, that starts to fall apart. I guess I should assume it was one of those "digital" experts that designed the analog section.

jason_k201713 posts11-04-2019 1:43pmThis is so very frustrating. I came on hear to ask a simple question about a digital switch and all I get is people trying to show off their extensive but completely irrelevant knowledge of old technology hurling abuse at me to cover their total inability to answer a simple question

I have moved on from analog. All of my source is digital. None of the stuff that several on here are trying to impress me with from their presumably vast experience in analog can change the stream of ones and zeros into a different stream of ones and zeros. No crackles, rumbles, glitches, interference from non-magic cables and power supplies. Nothing, zilch.

I am sorry if the digital revolution has made a lot of your knowledge totally redundant but that is progress.

I would respond, but unfortunately I have bullshit all over my shoes.

You know what people don't claim a 164 IQ in an internet discussion?  ... people who actually have a 164 IQ. They don't need to because it is evident in their communication.

I would save your lies for people who won't call you out on it. If you had an IQ of 164, that would place you approximately 1 / 100,000. Your reading comprehension issues are clear indicators that that is not the case.

p.s. that would be:

• 70s , not  '70s
• highest level, not higest
• Oh, but I forgot 
  

So let me get this right. You have an IQ of 164, but you were part of the test group?


It is interesting that you were "part of the test group in the early 80s. So exactly which group was this?

jason_k201714 posts11-04-2019 4:25pmActually no. I was lecturing on modulation techniques in digital communications in the '70s. I was part of the test group for Quadrature Amplitude Modulation utilizing Trellis Encoding in the early '80s And my IQ of 164 got me into the higest levels of military technology development

Oh but I forgot...........   I am ignorant

You said it very clearly, and concisely almarg, but unfortunately, someone was choosing not to listen.

almarg9,134 posts11-04-2019 5:54pm
I had said as follows in one of my posts dated 10-29-2019:

Can you tell me how many of those devices reconstruct a 100+ db dynamic range analog baseband signal?

jason_k201714 posts11-04-2019 4:25pmYou must try to understand that almost everything can introduce EM/RF noise. Every single device from the audio server, through every device my audio passes through on the internet and then my exchange to my router to my DAC can. Dozens and possibly hundreds of devices. But none of those sites think it necessary to use a magic cable or a magic switch. You really, really ought to attend a course on digital audio, or research it yourself.

Jason, jason, jason:

You got the answer you asked, repeatedly, from many sources. What you did not get is the answer you wanted, and the one that agreed with what you had already decided before you asked.

For all your claims of intelligence, as opposed to calling others morons, you illustrated not one iota of knowledge about the topic of the discussion. You kept repeating "digital is digital" which no one in this thread was disagreeing with. Why did you keep asking it?

What is really strange, now, is that you said **YOU** were the expert, 164 IQ and all. And yet, you said something like this twice, "To be honest when my EXPERTS replied to me regarding these nonsense products they did also warn me that I would find idiots like him on any ‘audiophile’ forum."

If you have "EXPERTS", then why are you here, on a consumer audiophile forum, looking for answers and calling other people idiots? I don’t come on here looking for experts in digital communications and analog reconstruction in potentially noisy digital systems. That is what engineering forums are for. This obviously is not one.


I have no illusions I am always right and if I did, my wife would be sure to remind me that i am not. However, I will go out on a limb with a hypothesis that you did come here expecting to tell everyone they are wrong, but you ran into people who know enough and are confident enough in the topic (at a technical level) not be bullied on it.


The floor is always open if you would like to share with us your deep knowledge of analog electronics and noise control in mixed analog / digital systems as this topic has almost nothing to do with digital communications no matter how often you tried to bring the topic back to it. If you read this thread there are many hints on aspects of the topic that could be discussed, even some hints on how the packaging of digital data can have an impact on analog noise.

jason_k201715 posts11-04-2019 5:44pmI am truly sorry to all those in here who were trying to give me a sensible answer. All I wanted was a straight knowledgeable answer

But I really can not put up any longer with this ignorant, jealous moron atdavid

To be honest when my experts replied to me regarding these nonsense products they did also warn me that I would find idiots like him on any ‘audiophile’ forum.

Ok atdavid, I give in. You are the big man, you are always right, everybody else has to listen to you and your ears are so much better than mine, and your equipment is the finest in the world and you know ten times more than me about digital communications and...and...and

You have achieved your objective of wearing me down with your insults and general assholishness (did I spell that correctly?

and yes it was measured 164 (around 130 more than you, it would seem)

As I have my experts’ replies I no longer need to listen to his drivel

Bye

24 frame per second motion picture film when projected in a theater, as film, is flashed 3 times for each frame, by the projector. Each image is "flashed" 3 times during projection. Then move to the next image, flash it 3 times ...

steakster860 posts11-04-2019 8:39pm

atdavid103 posts
You know that "film" was flashed 3 times per second, which again was not ideal but an acceptable compromise.

Huh? @24fps, film would have 24 exposures per second. If you’re referring to pre-flashing or post-flashing the negative, those are totally different processes that are executed in the lab, not in the camera. Flashing is intended to fog the film and reduce the gamma. The Director of Photography, Vilmos Zsigmond, employed flashing on the movie, "McCabe and Mrs. Miller".

I guess pointing out some of the obvious would be useful (for some):

• TV and Radio stations are high noise floor environments. You are not exploring the limits of human hearing, so you can almost take those out of the discussion.
• They do care about EMI ... hence why they use balanced cables.
• Recording studios, TV stations, radio stations .... are ADCs, not DACs. A recording studio is for the most part, a single point ADC, and ADCs used in recording studios are well designed, expensive units, and aspects of those designs is to eliminate susceptibility to EMI. All those digital cables ... are transmitting digital data and that data is not being converted back to analog except for monitoring and mixing ... again, rarely plumbing the depths of hearing and if so ... to hear if any EMI or similar entered recording that may be picked up on playback.
  

No, I would just say you are a bit slower in the UK .....

Would you rather I said encoding of the baseband signal into digital and decoding of the baseband signal into audio instead of ADC and DAC? The baseband signal will be encoded once with an ADC in a studio these days.

After that it is all digital. It should have been pretty obvious from what I wrote that that is what I meant." In the distribution of a single radio programme, for instance, it will go through a number of ADCs and DACs for technical reasons before it is even sent back from the cloud for final distribution" ... I can assume you mean encoded digital data, not baseband encoding and decoding, which in the context of this whole discussion is, well, rather meaningless and pedantic without being useful as the parameters for noise rejection, data recovery, etc. are 1) completely different from baseband audio, and 2) not really even the point of most of this discussion.

Last, if you are going to be pedantic, you may want to figure out who your audience is.


Studios crept into the discussion because someone tried to use, erroneously, that "professionals", i.e. in radio and TV studios don’t care about this.

Leave Stewart Pinkerton out of this :-) :-)   While I don't agree with his methods and he is way too quick to jump (at times to conclusions) at everything he perceives as snake oil, he actually is a fairly experienced engineer and would have understood the arguments being made, and would have disagreed with those arguments, not gone off on a tangent that everyone agreed wasn't the issue 100 posts ago.

thyname342 posts11-06-2019 1:35pmFor some reason, David in UK sounds exactly like Stewart Pinkerton, self-proclaimed "slayer of snake oil" in all internet audio groups and Facebook. And the only "contribution" to audiogon forums since he joined yesterday, is this thread.

Of course he would not approve of the switch!!!   :-)

But, after reading this thread and seeing that almost no one is denying there will be no degradation of the digital data, he would not argue that point. He would accept that analog noise injected via Ethernet could happen, then scream there is no way it is audible.

This is a data sheet from a typical Ethernet pulse transformer for 10/100/1000-T


https://product.tdk.com/info/en/catalog/datasheets/090007/trans_alt_en.pdf?ref_disty=digikey

While common mode rejection can be 30-40db, the insertion loss, i.e. losses in sending an actual signal, are quite low, 1-2db, even at 100KHz. 1 transformer at either end, so 2-4db attenuation at 100Khz, which is not a lot.


The question is, how good were the circuit designers at either end in ensuring noise didn't get onto or coupled from the Ethernet "signal"?