@audioman58
While I agree that digital interconnects can make a difference in sound quality, it seems you have received a masters in pontificating from the university of I don’t know.
For devices like the FC1 and FC3 which are irreducibly simple devices, the chip and the analog output stage determine the overwhelming majority of sound output. A manufacturer of a large stand-alone DAC that fits on a heavy duty rack has a lot more tech to play with, not necessarily better in practice or implementation.
You haven’t been following the science of hearing and developments in technology over the past 20 years, maybe more. And I say that because you arrive at 20 bits when CDs are 16 bit, 96 dB, which is plenty loud for home listening. You really don’t even need all that dynamic range, so more is not automatically better. How loud is 100 dB? quite loud, and prolonged exposure to loud sounds will result in hearing loss, even if it’s from your system.
20 bits true bits available is equal to roughly 120 dB? That’s much too loud for anyone to listen, you’d go deaf.
Now in the DIGITAL domain, if the device is doing that processing in 20 bits and spits out a very clean waveform, then that’s where more bits make sense. That, and in audio production.
Now you’re making the waters even murkier by talking about i2s, BNC cables, digital cables... of course these things can impact sound. I never said they couldn’t or did not impact sound.
Forget about looking at my system for now. Seems like you need to go back to school.