Well it hasn't been quite 24 hours but here's what I'm experiencing now...
When I first laid 2 iQSEs on top of my amp, I really didn't discern any difference after 24 hours. My amp has a carbon fiber top plate. Whether this interferes with the iQSEs' effectiveness, I don't know. When I placed them inside and 24 hours later, I heard an increase in soundstage depth and width and bloom. Listening to my go to lp for system evaluation, Shawn Colvin "Steady On", I heard more inner detail and the most enjoyable soundstage presentation I've experienced so far with this lp that I've owned for 20 plus years. On Eleni Mandell "Artificial Fire" (lp) which I always thought was bass heavy to the degree of being somewhat muddy, is still bass heavy but the bass is cleaned up, intellegable and very easy and enjoyable to listen through.
Listening today with the 2 remaining iQSEs in my phono preamp, the most stunning thing I hear is a perceived volume increase. On Peter Case "The Man With the Blue Postmodern..." (lp), the acoustic guitar strings have greater purity of tone with tonal colors that are very intoxicating. On Eva Cassidy "Songbird" /S&P/lp ...this recording is more beautiful than ever before. Easy to just get washed up into the vacuum tube aspect of this remaster. On Chris Isaak "First Comes The Night" (lp)....I'm a big fan and just bought this lp to complete my collection. I listened last weekend and was disappointed. It seemed to be lacking "soul" that most of his earlier lps possess. Today, I'm tapping my feet and really digging it.
I can't say if the order in which I evaluated these in my system had any impact on which piece had a greater effect. I would say they seem to remove noise that would otherwise distort the music. I'm just glad I have them in place now. I'm tapping my feet again.