Sealed vs Ported Subwoofers

Duke, Nice accurate explanation. Still unless you have the ability to build your own subwoofer that you can factor your own in room response.... Normally if you built a Sealed sub with a finished Q of .5, most people would say that it had no low end output. It would be extremely tight and in the right room would be superb. Manufactures have no choice but to build subs as accurate as possible, then we are forced to deal with room interactions, which are all different from each other. Ideally a sub would come with some sort of built in rta, mic and eq circuit. We do see many subs with a low end boost, but as you alluded to, normally a filter network would be just as valuble if not more. Tim

Sealed or ported both have benefits and - aspects to performance.There are ported designs that outperform sealed as there are sealed designs that outperform ported. The total design of the average subwoofer system is all about compromise. Cabinets overly small,as are most transducers drivers need massive excursions power and reinforcement from room boundaries due to the undersized nature of such compromised designs. A big reason why most do not work so well in music systems..

Tekton has a neat looking design that is quite novel. Its a sealed sub with a second driver on an open baffle on pillars a few inches directly in front of the other driver. They move in tandem, but not isobaric because there is no sealed airspace between them. Looks very interesting.

The sealed sub absorbs the backwave of the open baffle driver. Not really a new idea.

>The sealed sub absorbs the backwave of the open baffle driver. Not really a new idea.

Not exactly.

When you add a monopole and a dipole together you get a cardioid with 4.8dB directivity (versus 0dB for a monopole) which interacts better with room modes than the monopole.

If the engineers have done their job right, their sub-woofer should become monopolar at low frequencies (you're not gaining anything below the room's fundamental resonance, and a dipole's excursion has an additional doubling for each lower octave you play) so you're not loosing low end output as you would with a dipole (that also has 4.8dB of directivity)