what amp to power 2 M3's

I am debating on which amp to power my 2 15" drivers. each sub is rated at 400wrms. I have a jbl600.1, should i use this amp? I hear it puts out about 700wrms. Or should i go ahead and buy a 1000D from memphis? and be over powering the subs by 200wrms. They say u can pound the M3's with more power than they say. Any suggestions?03 F150 on 24's

HU:Pioneer DVD5700

Frt:MC57

Subs:(12)S12L7

Amps:(3)KX2500.1's, MC-2004

The JBL600.1 is perfect for your subs. While "they" might be correct, "they" usually don't know what they're talking about either. The SPL difference between 700w and 1000w will be inaudible, especially when the woofers are only rated at 800w. That upgrade wouldn't make any sense, in my opinion. New Project: 2003 Pathfinder

I also had another question. On the recomended enclosure sizes, for a vented box, it says to make the port size 4x5.5 inches. How deep do i make the slot port??? Also i just want both slot ports to be right in the middle of both subs. and the length of each port to be the height of the box. if anyone is confused i can make a drawing on paint. 03 F150 on 24's

HU:Pioneer DVD5700

Frt:MC57

Subs:(12)S12L7

Amps:(3)KX2500.1's, MC-2004

 the JBL600.1 should be plenty. you can push the subs over their power limits as long as you have little to no distortion. but kfr01 is correct you wont hear a difference. as for your port  the length depends on what frequency you want to tune the box for. the most accurate way to find this is theile small perameters, or call the manufacture live like theres no tomarrow because today may be your last.

Wow, yes, especially stick with the lower power if you plan on running ported. Use the same port depth (5.5"). Make the area of the slot rectangle the same as the area of the port circle. Area of circle = pi*radius^2 = 3.14*2^2 = ~12.5in^2. So, if you want the port to be tall and thin, you should do something like 12.5in^2 = .75in x 16.7in By 5.5in deep. However, I notice you're using a tuning frequency for 15" drivers at 38hz. This is way too high, in my opinion. I know this is what the Memphis spec sheet says, but I think it is crap advice. I feel like you should shoot for 30hz or lower.New Project: 2003 Pathfinder

should i use winisd to make my box? 03 F150 on 24's

HU:Pioneer DVD5700

Frt:MC57

Subs:(12)S12L7

Amps:(3)KX2500.1's, MC-2004