need advice on a new amp

I have a new Rockford fosgate T0d212. so of course i can run 1 ohm or 4 ohm. I have it installed in a 2011 Chevy camaro with a ported enclosure from subthump to fit the camaro. 1.9 cub before woofer desplacement. I chose this sub because my local shop gave me a great deal traded my 5 yr old p3 and 99.00 for the T0. very good deal. right now I have a brz 1200.1 I clipped the first sub and blew the sub. smoked it pretty bad. I thought it was on fire. I am thinking the amp may not be giving me the clean power I was hopping for. I was looking at maybe a rockford fosgate t1000-1bdcp that would give me 700 at 4 ohm or maybe I should rethink the way I set my gains. I used a 60hz zero db sine wave and a dimm. calculated 700 sq root is 21.45. set my stero to 28 of 40 wich to me sounded very clear and no clipping I could hear.  attached the dimm and turn up my gain until I reached 21.40. no bass boost on amp or hu. Still smoked this sub. my new sub will arive anytime from rockford. Any ideas would be great.

700 watts into 4-ohms would be approx. 52 volts output. (Square root of power times resistance.) Are you reading AC volts? Do you have the woofer disconnected when you set the gain to the proper voltage? If you are burning voice coils then either the woofer really cannot handle the power, or you are setting the gain incorrectly, or you are turning it up past the point where you set it, or the amplifier is defective and is producing DC.Support the12volt.com

I have it at 1 ohm now on the brz1200.1 no I did not have the subwoofer connected. maybe the new Rockford sucks. I tried to set the gain by listening to any distortion. but I could not hear any distortion with this sub and amp combination. I could not tell a difference in sound of the base.

Why are you setting gain by listening if you are setting it using the output voltage method? And clipping is not the same thing as "distortion." You can clearly hear the sound of clipping as the tone will change when the device starts to clip. To use a music term, it sort of goes flat. Did you read the "How to set your gains" post in the Hot Topics section?Support the12volt.com

I tried to listen and set the gains. I understand how to do it. I have never had a problem in the past but this sub and amp combo . Sound is the same all around just louder and harder. I'll just call around see if I can get someone with an o scope. Thanks bunches