I'm pretty sure this is exactly what Boom 2 does. https://itunes.apple.com/us/app/boom-2-best-audio-enhancement/id948176063 https://itunes.apple.com/us/app/boo

I'm pretty sure this is exactly what Boom 2 does. https://itunes.apple.com/us/app/boom-2-best-audio-enhancement/id948176063 https://itunes.apple.com/us/app/boom-2-best-audio-enhancemen... Note their reference in the description to an 'optional component' that enables system-wide effects.