USB powered speakers

[garnerb350]

Hey Guys got a question....

Friend of mine gave me a set of computer speakers that powers up via USB. I was thinking of maybe tying them in to my cab to hopefully add some more "umph"... there are two cords (1. input jack. 2. USB cord)...I am wanting to see if i can fix it where they wont draw power from the PC. Correct me if I am wrong...but if it get power from USB ...isnt that 5v for juice? I have an old wall charger to a cell phone...I belive that it sends 5 v to charge the battery in the cell phone. Can i splice it in to the usb and have it plugged in the wall socket for power? the speakers are here...

http://www.alteclansing.com/index.php?file=north_product_detail&iproduct_id=bxr1220
and the phone charger is ...
http://www.amazon.com/Charger-VX10000-VOYAGER-CHOCOLATE-UTStarcom/dp/B001IND46U