In response to your question Ted,
I do think measurements are critical, but measurements do not always ensure the best sounding product. That is my experience.
If we take the case of the Border Patrol DAC mentioned here, its tube output stage, right? Tubes do bring a very appealing sound, and can add a touch of euphony. It measurements are said to be not that good. But that color can disguise a deficit in performance in other parameters.
The integrity of source signal / the streamed file , is critical. A DAC and amp that measures particularly well, and is well engineered to drive the source with a robust, complete signal, will sound right with an excellent signal. The problem is that so many recordings, or streaming services can fail to deliver the perfect signal. Thats when a product (such as the Border Patrol) can add some color and sound / and feel more involving.
Yes everything matters to ensure the best possible signal transfer without loss. My experience so far is that digital coax cables really do sound different. I have not found ethernet or USB cables to sound different. Then again I have not heard a high-end USB cable yet.
BTW I have The SR Music Cable DAC (which is a great sounding little DAC), also foundation speaker cables (3mtr) and cable risers (set of 4).