Creating Audio Book App Icon

I was approached by app developer Vlad M. to help him with the icon design for his Audio book app.

LOGO IS YOUR COMPANY REPRESENTATION. IT'S IMPORTANT. YOUR BRAND DEPEND ON IT. HIRE ME TO DESIGN ONE FOR YOU

Version 1

Open book, sound movement...

Version 2: open book with headphones ...

Version 3: circle, pile of books, start button...

Version 4: open book in blue circle with sound images streaming as rainbow (a,b); closed book in blue circle with radiating sound image (c, d)

Vadim liked the first version 1 c the best but wanted to see it with different sound movement

And the finalist is... 1-5d