@atdavid, thanks for your thoughtful and knowledgeable comments on my post.
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.
Very true, of course. But I would expect that once the spectral components corresponding to those edge speeds reach high enough frequencies, whatever “high enough” may be in a specific case, increased amplitude of coupled “noise” would be outweighed by decreased ability of the circuitry to which it may couple to respond to those frequencies.
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.
Putting my response simply, none of this stuff is perfect :-)
Putting it less simply, I have no specific knowledge of the differences in impedance (and also bandwidth) that may exist between various off-the-shelf Ethernet drivers and transformers, e.g., what the +/- tolerances on those parameters usually are. But I would assume it likely that the +/- tolerances on impedance are wide enough to potentially affect the spectral characteristics of VSWR-related waveform distortion, with the length and impedance tolerance of the cable connecting the network switch to the audio system probably also factoring into those characteristics. And consequently the spectral characteristics of “noise” corresponding to that distortion that may couple into susceptible circuit points may vary as a function of the particular network switch, the cable, and the receiving transformer and its surrounding circuitry. With variations in the internal physical layouts of different designs conceivably also having significant consequences.
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.
If I understand your point correctly you are implying that coupling of data-dependent “noise” into susceptible circuitry has a greater likelihood of being audibly significant than the contributors I mentioned, namely spectral components corresponding to risetimes/falltimes, waveform distortion, and noise per se. And if so the likelihood of there being audibly significant differences between network switches is lessened (or perhaps even eliminated) since the data would be the same regardless of what switch is being used.
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 matches, 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.
The bottom line, IMO, is simply that the reported anecdotal evidence supporting the notion that network switches can affect sonics to an audibly significant degree (examples being the two cases I described in my initial post in this thread, which were provided by members for whom I have developed considerable respect over the years) does not seem to me to be beyond the bounds of technical plausibility.
In any event, welcome to the forum, and thanks again for your thoughtful and well stated inputs.
Regards,
-- Al