I am providing sound at an outdoor wedding. I have an L1S. I will only have a couple lavalier mics and a line for recorded music running.I'll leave it to you to do the math and factor in inefficiency in the inverter and how much you are willing to deplete your batteries.
Be sure to run a test for at least as long as you'll need, before you do the event. I have 480 amp-hours of Batteries running a 2400W Pure sine wave inverter. Will I have sufficient power for a couple hours of run time?