sub and amp question

      I have a us acoustics usx 2100, 100 wattsx2, I'm running 2 8" pyramid subs presently I would like to bridge the amp to 300 mono, to push a 12" sub. I have looked around and researched many different subs. The Crutchfield catalog rates the infinity kappa perfect @ 75-350 watts rms. The other day I was at my local audio store and asked the guy and he said I would not be happy with that setup. He said I would be underpowering them. Again crutchfield says to match a sub to an amp the amp should be in the upper part of the range of the sub,so I thought it would be a good match. I would like your opinion and or suggestions on what I should be looking for in a sub for that amp. I own infinity kappa 4x6 plate speakers up front and the infinity kappa 6.5 3 ways in the back and I like them very much, good volume and clarity. That is why I would like to stay with infinity for the sub.I own a van wich is hard acousticaly to outfit. I have considered  just the plain 12" kappa but I really like the perfects.I would consider any brand tho. Please give me some advice and insight        Cosmic Charlie

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Cosmic Charlie

The Infinity Perfects sound very clean if you bridge that amp to 300 watts you should be fine running the Perfect. But the guy at the shop was not wrong either the sub could use a little more power. It all comes down to if you want to spend the money then yes get a new amp but it’s not essential.

The kappa perfects can handle much more than 350 watts RMS.  If your budget permits it, I'd get those instead of just the regular kappas as they sound much much better in my opinion...not to mention they play deeper and can handle more power.