Originally Posted by Linkwitz Riley
I am very picky about SQ when it comes to subs. I don't necessarily need to blow out the windows (although it is fun to crank it on occasion). I have always seemed to favor the sound of sealed subs at home and in my vehicles. I like really tight, accurate bass and listen mostly to artists whose style contains that type of sound (Steeley Dan, Telarc recordings, tight jazz fusion, etc.) I have had ported subs in the past and while I found them to be perfectly acceptable especially when: #1
- the music was played loud and #2
- the music was less critical (hard rock, etc.). Recently I purchased a new set of nearfield studio monitors (Adam A7X) which are ported, and I absolutely love them and do all my critical listening with them now. While they do not produce any sub-bass, they are extremely accurate at all frequencies and volumes that they can play. So I guess with the correct engineering it is possible to achieve great response from both designs. I am currently in the same dilemma as you (in a way). I currently run 8 18" sealed subs but am considering switching to a pair of ported subs (Captivator 4000ulfs) for a 10K cu ft space with 17ft ceilings. I'm also wondering about the difference in sound.
But to get back to your point...I feel that for MOVIES your sub choice is much less critical. For a large space I would look to ported subs with low extension. Output and extension are the 2 factors I would consider for mostly movie use, and ported designs are an easier way to get you there in a large room.
I agree with your advice to the OP! I won't try to comment on any potential difference in sound quality between your current sealed subs and the dual Cap 4000's you are considering. I honestly believe that impressions of sound quality can be too subjective for other people to be very helpful to each other. I do, however, think that many people would experience some fairly serious differences in overall performance in making the change. Aside from sheer low-frequency SPL, the biggest difference would be in tactile sensations, in my opinion. And, that is really what the OP has been asking about. Not the difference in SQ between sealed and ported, or even in low-frequency SPL, but the difference in feel
between the two. I believe that there is a difference in tactile response, and that it is measurable.
This a link to one of several threads where people have measured the difference in tactile output between sealed and ported subwoofers: https://www.avsforum.com/forum/113-s...st-thread.html
From the perspective of low-frequency SPL, and anecdotally from the standpoint of tactile response, the ported Cap 4000 ULF's are right at the top of the food chain. People who have compared the various modern Captivators with other ported subwoofers, have specifically noted the extreme tactile sensations they create. As alluded to in my first post, we aren't talking so much about mid-bass tactile sensations here. Chest punch seems to be primarily the product of sheer SPL, unless we are talking about an MBM with a mid-bass port tune.
But, within about an octave of its port tune, two things happen when a ported sub is pushed a bit. First, the excursion of the driver increases and more air is moved back-and-forth. I am talking here about the physical movement of air particles, and not just the pressure wave created by sound waves moving through
the air. Second, the port itself moves more air, producing quite noticeable port wind at more extreme volume levels, and that also causes particle velocity. The Cap 4000's, with their extreme motor strength and excursion, and their ability to move air through the port, seem to excel at producing powerful low-bass tactile sensations. And, the Cap 2400's aren't too far behind them.
So, I tend to leave sound quality selections strictly to other people, since our subjective impressions may all be a little different. But, when someone specifically mentions wanting to feel more overt physical sensations associated with low-bass, such as thunder and explosions, then I immediately think of powerful ported subwoofers.
Incidentally, even with powerful ported subwoofers, there is no substitute for the real thing. My ported subwoofers can literally run me out of my large room, with the right subwoofer boosts, combined with the right movie. And, it's not just the low-frequency SPL, it's the tactile sensations that can be overwhelming to me after a while, if I really crank things. Batman Versus Superman
is a good example of that for me.
But, my house is very sturdy and it's on a concrete pad. And, even at very high volume levels, I have no issue with transferred vibrations. The other night though, we had a very powerful thunderstorm, with lightning striking much closer than I would have liked. And, my whole house shook violently from the impacts. Now, there's realism!