Play the same source back to back between A and B, and it's incredibly easy to tell the difference between two different amps, speakers, CD players, record decks and even cartridges at various price bands. Frequently it was far from subtle, but quite extreme, particularly at the cheaper end, but still quite easy between £2,500 components (or cartridges in the hundreds).

The question as to which was more accurate, or which you prefer is an entirely different one.

Now I could never tell any difference between £5 standard interconnect and £100+ directional silliness, or beyond QED standard £1/m speaker cable. Needless to say I never bought any of that. So I've never understood the appeal of lunatic territory with £5k mains cables that look more suitable for mooring a ship.

Reasonable people can tell the difference between 600/300/100 speakers or amplifiers. Up in the audiophile range, the difference between a $20000 amp and a $2000 amp is mostly placebo effect.