What's the fastest way to level up in dungeon defenders?

What's the fastest way to level up a lvl 57 apprentice and then other low level characters?What's the fastest way to level up in dungeon defenders?
Endless Spires on Insane first 2 waves dont let the monsters hit you or the crystals and you get just about a level every wave (that is if your level 50 or so)What's the fastest way to level up in dungeon defenders?
If you have some skills I suggest going to the first place (Deeper Wells) and put it on the highest difficulty then find out which combination of towers and attacks works best for you. This method also works for leveling a lower character. I was able to solo this on a 15 hunter so you shouldn't have any problems:)