Re: Should I have my amp repaired or buy new?
Regardless of what amp you end up using you should do some due diligence and find out why you keep burning up amps.
Improper gain settings usually wipe out subs so I'd start with looking at electrical. You said you have a big three done but that doesn't help if the alternator and battery you have aren't able to send enough power to the amp. Likewise with fuse and ground connections. Ergo, you can have the best alternator and battery(s) possible but if your connections are bad, so will be your electrical supply to the amp.
If you don't have zero gauge power wire, I'd get it. You can use reducers at the amp if your amp has 4 gauge inputs but for anything over 1500 watts you will see an appreciable benefit from 1/0 wiring. Also, make sure all of your cable terminations are sound. That means the crimp/solder points on the wire as well as the other end of the terminals. I would also replace the power line fuse and if you have a circuit breaker, toss it an put a fuse in its place.
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