I have 2 12" Alpine SWS-1242D type S subwoofers. I have them in 2 separate sealed enclosures. I was wondering if they would sound better if I got a different box. Should I get a ported, or bandpass, or just 1 sealed box for both of them, or wut? Which would sound best? What is the difference between all of them?
2 separate ported......why? The Type S will sound best sealed. Won't sound any different in a single sealed box for both. You would gain 3db (higher SPL)going from sealed to ported (typically) and loose SQ.
Not necessarily, a ported box can sound just as good as a sealed box if designed properly, and get more output. Key to SQ ported is a low tune, a smooth rolloff on the enclosure(aim for a rolloff similar to sealed, just with higher output), and a big enough port that port noise and group delay isn't an issue. It's all about personal preference, but great results can be had with either. If total pure SQ is what he wants, sealed is easier to accomplish and usually still a little better than ported, though, and the key to this is proper box size and building the box like a TANK, bracing is a necessity, as well as a good seal on the box so no air leaks out(ported boxes need to be built the same, they actually need more bracing b/c internal box pressure is higher in a ported box). Polyfill can help too as it can cut down resonance. Forget bandpass altogether for SQ, just a one note wonder SPL box.
Well the type S's aren't really known for their SQ to begin with u know what I mean. They are already kind of loud. Am I gonna loose a lot of SQ if I put them in a ported box? I mean would the gain of SPL be worth the lose of SQ?
Totally subjective, and limited to your opinion, if you want them louder w/o a huge loss in SQ, ported is for you. A lot of people give ported boxes a bad reputation because of the typical Best Buy ported boxes, and hearing SPL guys that tune extremely high and get a huge box size, but 99.999999% of these boxes could have been designed better from a SQ standpoint. Sealed boxes allow more of a margin of error compared to ported, it's harder to screw up a sealed box, ported is more temperamental. If you're a SQ extremist and want the absolute greatest SQ offered, sealed is more than likely the best option, they're also easier to build and design. If you're wondering if the subs ported will sound like crap compared to the sealed, no, it's not that drastic of a difference. You may notice a tad more boomyness, but that totally depends on tuning frequency and box size. Forget 40 hz and above for sound quality, these are strictly SPL tunes. If you tune 35-40 hz, it'll have a fat bump in the response and can get very boomy, 30-35 is typically considered to be the best of both worlds, good output, good SQ, just a well rounded tune. 20-30 is SQ region, and will offer great SQ with added output and more low end authority than a sealed box. 20 hz isn't typical in a car, b/c of the resonant frequency of the sub, which is usually somewhere between 20-30 hz, and also because 20 hz requires a really long port, most ported don't go below 28 hz, you will usually see 24-26 at most. Remember that this above is general and won't mean jack if the box isn't the proper size, too large of a box will result in a boomy response, and too small will result in bad low end extension and a roll off in frequency response. It also depends on the subwoofer being used. For a SQ ported box, like said above, you need to tune pretty low, use a large port surface area (this is best for SQ and SPL actually), it also works to try to simulate a rolloff somewhat similar to a sealed box. Programs like WinISD pro are great for designing ported enclosures. Ported boxes aren't all bad, look at high end home audio equipment, you'll see more ported enclosures than sealed. A lot of this is because a room doesn't have the gain of a car, but it proves that ported isn't a detriment to SQ if designed correctly. Note that home audio ports are low tunes as well.
so lets say I get a ported box tuned to 35-40 hz. Will that make a very noticable difference in my SPL? And will that make a very noticable decrease in my SQ? If I get a box tuned to 30-35 hz, is that going to make much of a difference in SPL?