I am looking to buy two alpine type r subs that have 500w rms each. What kind of amp should I be looking for?

 

You need to nail down the type of speaker first as that will determine your choice of amp. Dual 2 ohm coils = a mono amp that makes it's rated power for your subs at 2 ohms. Dual 4 ohm subs = a amp that makes it's rated power at either 1 ohm or 4 ohm. You will have a much larger selection of amps with the dual 4 ohm sub choice. Your budget will then determine the amplifier.

 

I was looking at 2 Alpine SWR 1242D subs. They have dual 4-ohm voice coils. The Apline pdx-1.1000 mono amp has 1000W rms power at 4 ohms but $500 is a little more than I want to spend. Unless the pdx-1.1000 is really worth it, I would like to spend less than $300 on the amp.