TT5, My current understanding on this topic is you want to make sure whatever sub you buy has a fair amount of flexibility to tune it (which can also come from the AVR or a miniDSP, etc).
According to Josh Ricci, the measurable characteristic that most contributes to "articulation" or a "fast" sub is having ratio of higher frequency energy to low frequency energy.
WIthout involving DSP or other manipulation, and just looking at their natural FR tendencies:
The sealed sub will have a higher ratio of high frequencies compared to the lower frequencies! The problem is a plain-jane sealed sub simply does not offer as much deep bass as you would generally want.
Happily, with a stout driver and enough power, and the right tuning/DSP, you can get significant deep bass out of a sealed subwoofer.
The ported sub has a very strong boost in efficiency at (and near) the port tune frequency which equates to a boost in SPL at the port tune frequency. It takes care to tune a ported sub so that this port tune frequency is not overbearing (thus the comments about fart boxes)!
Happily, modern ported subs from the preferred companies here are well tuned to avoid this being a problem.
But, even better, most of the subs from companies like HSU, SVS, PSA, Rythmik, Outlaw, etc offer a reasonable amount of control over your final frequency response, and I believe that most of them will allow you to get a ported type response out of a sealed sub and a sealed type of response out of a ported sub!
This is important because you don't know what a room is going to do with the lower frequencies! Let's set aside the effects of room modes (because that is generally not the purview of the tuning capability of a typical sub). If you have lots of cabin gain, a typical ported sub with a ruler flat
anechoic FR can get boomy and lose any sense of "articulation" because the actual FR in your room would be bottom heavy! Obviously, you want a flat response in your room, not in an anechoic chamber! Conversely, a typical sealed sub in a room with very little cabin gain is likely to be deficient in bass.
One of the best examples of this I have come across is Josh Ricci's review of the PSA XS15SE where he says:
Frequency Response
The basic frequency response shape with the low pass filter bypassed shows a response that is cleanly extended up to 200Hz and beyond, with a gently sloping low end that corners at 30Hz and appears to enter a sealed systems natural 12dB/octave roll off below that point. It should be a good match with the boost often seen in the low bass once placed inside of a room. It appears that there may be a bit of boost employed near 35-40Hz to extend the corner downwards a bit. The overall response with the low pass filter disabled fits within a 6dB total window from 28-370Hz.
Because the PSA XS15SE was the second subwoofer that worked really well for me (after the Rythmik E15HP) I paid close attention to Josh's review!
He is referring to this "anechoic" FR (scroll down to the first two charts):
data-bass.com
Of course, the cabin gain you will get in your room is a wild card! Typically placing the sub in a corner will give you much more gain and moving it more to the center of the room reduces the gain.
Personally, my experience has been that Audyssey gets the bass about right
in my room! However, I turn the sub down ~2dB for music because every so often a song will be recorded with the bass too hot for my taste and I would rather have a slight bass deficit in most songs than boomy bass on those where the bass is recorded too heavy (IMHO)!
For HT, I turn the bass up by ~6dB for an action movie where I want to feel that low frequency power (muwahaha!) and giggle (tee-hee)!
Ultimately, it is a personal and subjective decision of how much lower bass you want vs articulation (that ratio that Josh attributes to "articulation/speed/tightness".).
But the take away is you want a sub that allows you to tune the FR enough that your AVR can do the rest (if you use Audyssey or similar). Ported or Sealed doesn't matter as long as the sub has versatile tuning options!
My JL Audio E112's are tuned to an anechoic response and I found that they were far too boomy in my room and Audyssey (which has a maximum limit of 8dB (?) cut or boost) could not compensate. So here we have a sealed sub that has been tuned much like a ported sub normally and it was boomy in my room! They are very potent, but they offer no ability to tune the FR, so I cannot make them sound good in my room without adding a miniDSP before Audyssey!