I use a Wharfedale Pro powered PA cabinet for keyboard amplification that has a handle in the side of the cabinet which is useful to grab to postition it for lifting. But face it, wherever you put the handle on a box that is 30+ LBs then it will be not only awkward but very bad for your back if you lift it from the handle. I learned from working as a roadie/musician for a number of years that it is always best to lift a box using both arms so you can walk upright without stooping. If you can get it up on your shoulder, then that is even better.