I mean, "grooves are grooves," right? Is one person’s system "broken" because it sounds different from another person’s system?
It’s a very different situation because the groove on a record hasn’t been transferred to an abstract definition during the recording process, while the digital file has been. Because of this, each vinyl record is a one-off, with it’s own set of unique sonic characteristics that weren’t intentional, but are indelibly intermixed with the intended signal. No mechanism was used to keep them separated, and no mechanism can tease them back apart.
Each copy of a digital file, assuming no errors crept in, is identical, because it’s a definition, not a direct analog representation. The server’s job is just to serve up that definition, and there’s no excuse for a server doing anything other than that because the engineering has been solved. Any decent cable will allow a bit perfect information transfer to the DAC, as has been shown by capturing the bits into a file on the other end of the toslink, usb, or whatever, and then comparing the sent file to the received file.
Jitter artifacts are typically below the audible threshold of mere mortal humans even on $8 dacs running a synchronous signal through a cheap digital coax.
I think it was on this forum that I read about a guy who was playing test tone LPs, and noticed that something as simple as a sine wave sounded better from LP than from CD. When he analyzed the waveform, the CD produced what looked like a nearly perfect sine wave. The LP produced something only vaguely similar to a sine wave. It added a lot of other stuff, which is why he liked it better. Pure sine tones aren’t pleasant sounding if you ask me.
So no, there’s no equivalence between saying ’bits is bits’ and ’grooves is grooves.’ Because bits is bits when comparing two copies of the same recording, while grooves ain’t. They’re just very similar. And different cartridge designs are going to result in much larger output differences than different dac designs, assuming the dacs are all reasonably competent, and the vast majority are. From what I’ve seen, the most suspect ones are the most expensive and least expensive.
This is why I would say that if server software is producing a different sound, something somewhere along the data chain is not working to specification, or there is some intentional DSP going on to add some kind of effect to make the server sound different than it would if it delivered an accurate file to the DAC.