what i understand.
Sealed= punchy, clear bass, most freq response
Ported= deep, slightly blurry bass, more Db
Bandpass=very loud, low freq response

is this right?

would it make sense to build a bandpass box for db drags and keep a sealed box for daily use?

each woofer has a prefered box type. Some woofers can sound punchy even in a ported box, should be fine for daily use aswell.

Rhyso

Well executed ported boxes can sound far better than sealed boxes, for these reasons:

1. You can contour the response of the enclosure to suit the vehicle's acoustics
2. Ported boxes deliver the same output with less power and cone excursion
3. Ported boxes simply play lower and louder

The only draw back is that they are larger than sealed boxes. This is taken from a recent review in a major US magazine

"we opened the vent in the Audio Enhancers enclosure and slid in the port to tune it to 33Hz. This made a magical difference. Whereas we found the WOOFER tight and solid as a sealed system, the vented system was powerful and had a very satisfying weight at the bottom end of the scale. Technically slightly exaggerated, this response was -3dB at 48Hz, but had more energy just above the roll-off, and was just fabulous to listen to. A couple of musicians visiting the lab while this was going on had the opportunity to listen to the WOOFER in sealed and vented modes, and the verdict was unanimous in favour of the vented set-up"

Phil

so i build a ported box.
what about the bandpass for Db drags? can i use a bandpass box in compition?

ripped used a bandpass box in his Astra with lots of success.

you look pretty new to the forum..

I would recommend starting off with a sealed box, then work to ported....

depends on the sort of music your into as well...

if your into rap/hip-hop/rnb, as I am.. go for ported... 50 Cent wouldn't sound the same.. LOL

ideally you could go for a sealed box..

thats my input.. lol

Vented Vented Vented
Its the only box to build bar none.
If your after SQ. The ability to taylor the response curve to your cars response makes this design the only choice.

If you want to win SPL comps then build yourself a perfect sub/enclosure design. Measure its response curve in a paddock somewhere real quiet. Use a sweep from 14HZ to say 250HZ higher if you want. Record the results with 5 watss of power, then again at 10, 30, 50 and so on. Go as high as you want.
Then put the box in your car and repeat the process. You will and I repeat will find a FREQ that is higher than the others by a large margin.
Next, find yourself a sub and slam it into a band pass box tuned the the peak frequency you found in the in your tests. I can assure you that your comp results will improve.

If you want the best of both worlds, then sealed is a fair middle ground. However, in my experience I have found sealed sub systems to be mono tone no matter what sub you use.

Cheers

its not as simple as saying, im building thisd type of box. as rhysy said, each sub ahs its own "preferred" box type, and will sound better in it. But as phil said, ported can sound better than sealed, even if it is not the subs preferred box.

I have been running my IDMAX for the last 3 months, in a DIY 1cuft sealed enclosure, and then in a pre-fab w/ DIY-port, and for some songs( ported is infinitely better. Whereas for others, i found sealed reproduced the bass better.

Unless you can afford to build two or three different boxes, once you make a decision, you have to stick with it. or, if your smart, you can make it so that it is easily alterable. ie, has a "sealed vent" which can be removed, and a port incorprated, etc...

if any of that rant makes sense, i hope it is useful