Really, though...
I vividly remember well-respected audio writers on the internet (other non-professionals like me) who literally stated that the difference of some cable or accessory upgrade was "not like removing a light veil off my speakers, but more like removing a heavy horse blanket from them."
Now, if you've ever put a horse blanket over your speakers, I can assure you that the resulting sound is extremely muffled and barely audible. So, if the example of removing a horse blanket was meant to make a point - it clearly suffered from a rather extreme level of hyperbole. But what are we supposed to make of these sorts of statement?
I have been ranting an raving about the little, and often affordable, methods for making very real differences in how our systems sound (usually for the better) to help everyone get more from their musical enjoyment, for the past 12 years, yet I have to contend my realistic statements about the proper application of acoustic treatments to those who would state that some amp upgrade will "reveal clarity and detail from the speakers which they were not ever intended to provide." How do I talk rationally when people fill our heads with that nonsense?
So, this language question is VERY important to me.
Does a very good cable make a real difference? Well, there are actual measureable differences between a $1.50 RCA cable and a $200 audiophile cable which in some cases we might hear. However, I can guarantee that every time you swap your speakers for any other model, regardless of price, that you will not need some super-precision measurement tool to realize the HUGE difference in sound you'll hear.