sub and amp compatibility

I got an MTX 275x amp which gives 37.5 X 2 RMS at 4 ohm. I got subs which are 150rms and 8 ohm (rockford fosgate 8 inch RFZ3808) http://www.dealtime.com/xPF-Rockford_Fosgate_RFZ3808 Can I use these subs with the MTX 275x amp? what difference does it make when the ratings of the amp and sub or speakers dont match? i dont understand this impedence (ohm) stuff used for speakers. What does higher impedence mean in terms of sound?

You can use those subs with that amp, question is will you have enough power to run them without blowing them. From what I know the most common reason for subs blowing is not enough power. By "subs" do you mean 2 , 3 , 4, etc? Depending on the amount of subs you have would depend on the way you hook them up, and the way you hook them up will depend on what ohm your amp will be running which will determine the amount of power you use. check out https://www.the12volt.com/ohm/ohmslaw.asp to learn a bit more about ohms and stuff. You must also take into consideration of your amp and where it runs stable at. By that I mean some amps arent to stable at one ohm, for that matter some amps arent that stable at 2 ohm. Hope this helps a bit.

yes by subs I mean I will be connecting TWO  8 inch subs (both Rockford, 8 ohm subs) . I will read the basics and may be then it ll make more sense to me,. thanks.