You have Mac 452 and that's now mid? My how things have changed. Had a pair of MC 275s in '85 same happened . Kids with college degrees now. Back down the rabbit hole!
Moved Audio Quest cable to my DAC. WOW
I just moved my Audio Quest power cable to my DAC and noticed a more realistic open and better detail.
I have always been skeptical due to my electrical engineering bbackground.my wife also noticed a better sound.
The cable never really made any difference on my JC5 amplifier but maybe as someone else pointed out, power cords make a bigger difference on up front equipment with less sophisticated power supplies.
Ordered a linear power supply conversion for my streamer. Will see what that does.