Printer Friendly Forum Posts - 2 Alpine SWR-1222D + 1 Alpine MRD-M1005

Hey everyone, this is my first post and am hoping to gather some assistance from you all. I've done a lot of searching regarding my question, however I am looking for feedback from a more knowledgeable crowd, which brought me here. Excuse the length of this post, I wanted to provide all the information I could. Thanks in advance!

I just bought an Alpine MRD-M1005 monoblock amp, and I am going to be buying two Alpine SWR-1222D subs to pair into it. They'll be wired so the amp receives a 2 ohm load, so each sub will be getting 500W RMS. I've been leaning a lot toward a sealed enclosure, as I prefer tight and responsive bass that has a punch to it you really feel. Now, with what I have just said, you think the answer to my question would be quite simple right? Well, it isn't, because I see so many different facts thrown out there about sealed and ported enclosures that I don't know what to believe.

So, to the juice! I've heard that a sealed enclosure is good for what I am looking for, however it isn't very loud. I wan't my setup to really pound, not competition loud or anything like that (obviously not with what I'm getting), but loud enough that the bass wont be drowned by anything; this is of course while retaining SQ. With a sealed enclosure I've also heard that the efficiency isn't that good, or that it wears out a subwoofer quicker than a ported enclosure would. Is this true? With a 1000W RMS amp @ 2 ohms powering both of these subs, will loudness even be an issue with my subs in an sealed box? With this much power being put into the subs, is reliability in a sealed box an issue?

Basically, to sum it all up:

Bass Goals: Quality, tight, responsive, punching with good volume.
Concerns: Reliability, efficiency.

Now, to add some more technical information to the post:

First of all, this will be going in a 2001 Integra hatcback. That gives you a general idea of the space I have availalable, as well as acoustic factors.

Next, the Qtc of each subwoofer individually is 0.67. This would suggest better performance out of a sealed enclosure rather than a ported, correct?

Also, the F3 of each subwoofer individually is 51Hz. From what I've read, this is the frequency either above which or below which the power output of an amplifier is reduced to 1/2 of the passband power. What exactly does this mean, and in the terms of this subwoofer, is it above or below 51Hz?

I've also read that the optimal gross internal volume of a sealed enclosure for this subwoofer is 0.85 ft³. Is this true, or is a different volume for a sealed box more optimal?

So far, this is the equipment that will be set up:

(1) Alpine MRD-M1005 monoblock amplifier
(2) Alpine SWR-1222D 12" subwoofer
(1) Pioneer DEH-P680MP headunit

To end this post, the amp will be wired into series/parallel with the two subwoofers, for 500W RMS each. The amp will be hooked up to the Pioneer HU which has three preouts at 4V @ 100 ohm; this HU should offer a lot of flexibility for future plans. Component speakers and a seperate amp for them are down the road, as well with another set of components in the rear, or coaxials in the rear; haven't decided yet.

Thanks for all replies, input is much appreciated!

First of all... Always post as much information as you can. That is a very good post. Keep up the good work.

Second... Like geepherder said, you should stick with a sealed enclosure. Sealed enclosures offer plenty of "punch" and are much easier and forgiving if you're making the box. A vented enclosure will most likely be louder, but it takes up much more space. A vented enclosure also reduces the power handling of the woofer. You will also have to set up an LP filter to prevent the subwoofer from running into mechanical problems.

To sum it up you should stick with a sealed enclosure. To get the correct internal volume for your box you may also want to try WinISD. Take a look at THIS STICKY by stevdart.

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That's my opinion. Take it, leave it, or correct me.