Do you hate Boom's menubar icon? Yeah, me too. It's really ugly and so I decided to make my own. Now, this one doesn't change as you turn the volume up nor down. It's just one icon for all levels (I think it's better this way).
Installation: Just extract the .zip file. You will find a folder with my icons. Move them all to the "Resources" folder inside Boom's application. Easy as fuck!
I hope you like it