As a person somewhat new to digital music,
I was very skeptical at first; however, I've learned that cables do matter. Streaming Tidal in my system (NAD M12/M22 v2/Innuos Zenith MK2, Tannoy 8 dcti), I compared my stock USB, Ethernet, and power cables against moderately priced better cables of each. For my comparison, I started with all stock cables. I compared Tidal playing through the Zenith against Tidal playing through a Squeezebox Duet and through the NAD BluOS module.
Switching back and forth, I noticed an immediate overall improvement in SQ via the Zenith. From that point, I replaced the stock USB cable in the Zenith, and noticed an immediate but subtle improvement in SQ. Next, I replaced the Zenith's power cable - same result, immediate but subtle improvement in SQ. Next, I replaced the Ethernet cable - same result.
The better cables provided a better sound stage and I could hear more music, which leads me to believe that better cable provide more digital information. The better cables provided a warmer, tighter sound than my stock cables. In short, the music just sounds better to me, and others who heard my system before and after.
Switching back and forth, I noticed an immediate overall improvement in SQ via the Zenith. From that point, I replaced the stock USB cable in the Zenith, and noticed an immediate but subtle improvement in SQ. Next, I replaced the Zenith's power cable - same result, immediate but subtle improvement in SQ. Next, I replaced the Ethernet cable - same result.
The better cables provided a better sound stage and I could hear more music, which leads me to believe that better cable provide more digital information. The better cables provided a warmer, tighter sound than my stock cables. In short, the music just sounds better to me, and others who heard my system before and after.