Most of you have probably done this but i've had a Monster brand audio cable kicking around for a while and always wondered if it could be done. My GF-575 and D8614 both have line out/in points so i thought i'd give it a go. Plugged the cable in from the Philips to the Sharp and used a cassette adapter so my LED's still dance on the Philips. Rigged it up to my phone and pressed play. IT WORKED!!! so now I can use both boomers at the same time
Not exactly a tower of power but once i'd messed around with bass/treble/spatial settings I have a rather pleasing bassy sound. They both sound different but they kinda complement each other. 

