I have a hartke lh500 head. The manual says that if i am running at 4ohms, i will be putting out the the full 500 watts. Hartke recommends using a 4ohm cab with a minimum 600 watt rating. Now here is my question.. i was looking at a ampeg cab that has a 500watt RMS / 1000 watt peak rating. Would this be safe to use? Should i be looking for the RMS wattage to be at least 600 watts or the peak to be 600. I am confused... Thanks for any help.
That cabinet will work fine. It's really up to the manufacturers to specify whether they mean RMS or Peak. Some do it pretty well, and others don't. The good news is if you're close you'll usually be okay.