I recently purchased a pair of supertweeters from SMC (after gentle persuasion for them to get a pair in on trial), the results are amazing, as other people have discovered, you don’t really know how they work, but the effects are instant.
Even on setting 1 the soundstage opens out, quite how the low frequencies improve I can`t work out but they just do!
After many years of Hi-Fi “tweaking” this required very little effort and time in setting up, anyone who thinks that is a lot to spend on supertweeters alone think again, I use PMC OB1 speakers with a Rel sub, the addition of super tweeters means I have a A34500. speaker package, everyone who has heard them has said the sound is an improvement over many speakers which cost 2-3 times that amount.
Thank you for a wonderful product, I can heartily recommend them to anyone who loves music,even if they think their systems perfect!