peavey sp 2ti help!

I am a beginner DJ. I had a show at a restaurant this evening and I think I blow the horns out of my peavey SP2ti's. Everything seemed fine for my sound check at the start. About an hour in I noticed the horn in my left cab wasn't working in the full range jack. I moved the cord to the hi amp jack to see if the jack had gone bad and still had no horn. I tried to get through the rest of the evening but the right speaker lost its horn with a little less then 30 min. to closing. I know it is due to my inexperience that caused it but now I have to fix what I broke and figure out what I did wrong so I don't do it again. I think it had somthing to do with the way my rack mount crossover was set. It was set at 140 Hz because my PV Sub out front has that for crossover spec but the SP2's are suppose to be at 800Hz. I didn't use the bi-amp jacks because I dont know that much about bi-amping my speaker and thought it safer to keep it simple. Can someone please educate me on my delima?

Several things could come into play here. first, lets address the crossover issue. I would run the crossover frequency at about 100. The sp2's shouldn't be ran at 800. If you do this you are going to place a lot of muddy low-mid range frequencies in your subs. sp2's are designed to run as a stand alone box and will be just fine even without an external crossover. Secondly, your power amp capabilities need to be addressed. Are you running enough power on these cabinets? I would recommend at least 400 watts per cabinet. Having too much power is better than not enough. Picture this, if you don't have enough wattage to move the woofer in the sp2, the horn will get the brunt of the power being sent to the cabinet. I know this sounds crazy, but true. And last, and probably most important, you could be just simply running these cabinets too hard. sp2's are a very popular cabinet, but an entry level cabinet non the less. Try this arrangement and let me know how it works out for you. Run your crossover at 100hz. make sure you have enough power (no clipping of the amps), and just listen and make sure your highs are not too harsh. You are probably setting up behind the speakers so just remember, it's a lot louder in front of the speaker than where you are set up. hope this helps