Someone finally got me to try better cables and my sound quality jumped. It jumped again when I spent $500 on used $1,200 cables and jumped again at $900 for used $2,200 cablesActually, "Someone finally got me to try different cables and my sound quality changed. It changed again when I spent $500 on used $1,200 cables and changed again at $900 for used $2,200 cables."
The perception as an improvement is confirmation bias.

