Sub tuning (box) and filter freq

I've read alot about how to build the box for a given freq, like 32hz. How does this correlate to the amps filter.

The filter on the KX400.1 is 50-200hz. Should I build it to 50hz and set the filter all the way down to 50hz?? This sounds too high to me, but that's why I'm asking.

The amp will be running 2 12" Kicker Comp VR with 2ohm DVC (05CVR122) wired to a 2 ohm load. I'm planning the box now and will be building a ported or vented box.

If it matters, I listen to old school rock (Metalica/Scorpions etc) and looking for SQ with as much SPL as possible with this little amp.

Any help would be greatly appreciated! 

real SQ in a ported isn't really gonna happen, same with the vented.  As far as port or vent tuning, that determines which frequency you want the most volume at.  The amp's crossover will determine the highest frequency that your speakers will play.  If you're playing metal you would probably set your crossover between 80 and 120 Hz to get the kick drum and bass guitar.  In regards to your port tuning, that is entirely up to you but I wouldn't set it too low because it would be pointless with most metal.  I should also mention that it'd be a safe bet to use a subsonic filter with a ported/vented box as well since any frequencies below your port tuning can damage your speakers.

P.S.  If you really want SQ, I'd recommend a sealed box.

There is no correlation, so you don't have to take it into consideration.  You will have a limited amount of space in which to place a double-chambered enclosure...and you have a minimal amount of available power...so that is your first objective:  find the maximum amount of space available and design your box to take up that space.  As you can see in the MANUAL, this subwoofer can perform best in a larger enclosure.  Musical tastes don't matter as much as the power:subwoofer ratio that you are working with.  You will be supplying a limited amount of power and you will need to maximize it.  Use either sealed or vented with this sub, but take  your available space and power into consideration.  Vented will maximize the power available, and the larger size enclosure will add to that efficiency.

Use the amp's built-in subsonic filter (set at 25 Hz ...  MANUAL) whether you build sealed or vented, but especially with vented.  In the case of vented, you can tune the port anywhere up to 45 Hz, but tuning to the lower freqs will maximize the overall response, giving you more lower end.  The size of the box will be the determining factor;  the larger the box volume the lower you will be able to tune.  Use the guidelines in the manual.  The LP crossover can be set anywhere where you get the best transition of response to the midbass drivers, who also should be set with a corresponding HP point....usually 80 is a good crossover point.  With your musical tastes, the midbass will get a great deal of the responsiblity of kicking out the SPL, so make sure you have good drivers and powered with a clean amp.

You'll want to use as much space as available with either sealed or vented;  notice that the volumes shown in the manual include driver displacement, but not port displacement;  build the best sub enclosure you can without regard to your choice of music;  amplify your midbass drivers and tweak a good transition point with the crossovers;  if you build vented, use a slot port.

Excellent.  Thanks for the help!

Well, I went and got greedy. I ordered another KX400.1. This time I ordered it from Cardomain. They gave me a price very close to what Ikesound charges. Should have done that to start with, being as they're an authorized dealer..

So, I will have two that I can strap together. Now the question.....

I'm a little confused as to the power rating when strapping the two amps. According to the manual @4ohms output is 200 as a single unit. @2 ohms of course it's 400. When strapping them together you can only run a 4ohm load. What would the output be @4 ohms while strapped?

If anyone knows, I'd really appreciate it. (I need to order the right subs from my local shop).

Read and understand the TECH MANUAL in connecting the two amplifiers.  You see that the minimum impedance of the load must not be below 4 ohms....and you know that a KX400 amp is capable of a 2 ohm load.  Right?  So, reason will tell you that the connection of the two amps by strapping is the same as any parallel connection - the load will be halved so that each amp will produce output into 2 ohms.

Looking at the amp specs, the KX400 is rated to produce 400 watts into 2 ohms at full throttle 14.4 V.  Strapping two amps will double that to 800 watts to your 4 ohm subwoofer load.

It's very much the same principle as bridging a two-channel amp...each channel is a mono amp / each mono amp is a channel.  By strapping two mono amps you are creating a powerful two-channel amplifier.

I thought you already had the two subs, so that's good that you don't...they would have been wrong.  Get the DVC 4 ohm models.  Wire each sub's coils in series and parallel the two subs together for a total 4 ohm load.

It will be the same power output as if you put one DVC 4 onto one amp and the other DVC 4 onto the second amp (only in this case you would wire coils in parallel instead of series)....each amp powering a load of 2 ohms.  The main difference with strapping will be that the secondary amp's controls will not function, so you only have one amp on which to set the controls...just the same way a two-channel amp has one set of controls.

That's what I was hoping. It wouldn't have made any sense otherwise.

The subs I have are just an old crap pair.

On the upp side......the amp from Ikesound finally arrived. Two weeks to the day. I swapped out the old for the new in about 10 minutes. Works like a charm. Birth sheet says 465RMS. I'm using the old subs at 4ohms but still could barely move the gain off zero. Which is fine for now. The other amp should be here by Monday or Tue.

With this info I stopped at the local shop on the way to work. He suggested a 2 cu ft sealed box and a pair of P3's (12"). I was just worried about running over 450 RMS into the Com VR's which are rated at 400RMS. The P3's are rated at 500 each.  But they cost $250 a pop.

Now I have a tough decision....the Comp VR's or the P3's (man, those are monsters).........

Just an update:

The Cardomain amp arrived today. I just ordered it yesterday! The birth sheet shows 480 watts so now I'm thinking the P3 is the better match since the VR's are rated at 400 vs 500. I will be feeding them about 475 each(465+480/2).

So with 2 12" P3's fed 475 each (945 total), should I go with a ported box or sealed. Going for SQ with as much SPL as possible.