About 1/2 hour after install one of my infinity 6000cs is blown out.(4 ohm 90 w RMS / 270 w peak) I'm driving it with an infinity 7540A amp (111 watts RMS at 4 ohms) with xover set to pass 100hz and above. Do you really think i could blow out the speaker with only an extra 21 watts rms! What do you think? I think it was a defective speaker and plan to return it for a new one.
I think its your fault for pushing the speakers too hard after they were only installed for 30 minutes. Especially since you knew you were overpowering them. Infinitys 6.1 perfects can handle 111 watts rms, not their reference line. Break the speakers in first next time
It is pretty rare for speakers to blow from clean power. It is due to overloading with distortion/clipping. I never trust Alpine/Infinity amps. They are a bit over rated IMO. You'll be much better off with PPI's art series/PC/PCX or Orion's HCCA amps.