Thanks for the designs!
I like #59 as an improvement on #46, though the record is now almost too literal.
I'm not crazy about #58 or #60 because the speaker cones seem caught in between being literal and abstract, and don't appeal to me as either.
#62 and #63 seem a bit old-fashioned for my tastes.
In #61, I like the way the letters are arranged, but the graphic elements are not pleasing/arresting enough. I'm really looking for something that is not just evocative of what I do, but is also kind of a work of art unto itself.