I currently have 2 12" sub. This is the spec. http://www.mmxpress.com/Audiobahn/images/ABB122Q_sd.gif

Im thinking about purchasing this amp.

Pioneer Gm-D7400M Mono
Mono subwoofer car amplifier
200 Watts RMS x 1 at 4 ohms (400 watts RMS x 1 at 2 ohms)

Do you guys think this will be enough power?

 

If I understand that spec sheet correctly, the final impedence for the enclosure is 4 ohms? If that's the case, you'll only get 200 watts out of that amp. You don't have to give the subs the full 800 watts RMS they're rated for but IMHO you'd be happier with more than 200 watts.

You might want to look at 2 channel amps, you could bridge the amp at 4 ohms and get the most out of it. Most of the mono sub amps are 1 or 2 ohm stable so you'd be paying for power you wouldn't be using with this setup. A mono amp like that would give you the option to switch the subs out later for something that would wire to a lower ohm load and take more power, so it might be worth it to you. Even if you go that route, I'd still choose something more powerful than that Pioneer.

The Pioneer will work, you can run the subs off that power without problems as long as you set the gain properly.

 

The sensitivity of 99db is efficient. 200 watts should do well. More power will give more volume.

 

the speakers are more powerful than the amp they will make the amp work harder meaning get hotter faster and may blow fuses, you would be better suited gettting a 2 channel 400 watt amp

 

Not to be a jerk, but the power handling of the subs has nothing to do with how hard the amp works. How hard the amp is working and how hot it gets is dependent on the ohm load and gain settings relative to the input voltage.