Originally Posted by indebtbassfreak
I think i remember Tom from PSA (i could be mistaken) saying that subs also,,, down to a certain frequency will have similar results "as speakers" to the MLP regardless of the room depending on placement. It's the lowest octave's that can be lost at the MLP, as the ULF does see the whole space and if large will kill ULF at the MLP.
So if we were talking about a 6000^3 open room for example, and sub placement was quite far from the MLP,, then likely there wouldn't be much advantage to the 4000's extension advantage over the V-1811 imo.
Originally Posted by imureh
I am not sure about this myself, based on the hearing a 2400 ULF in a 7000^3 open room, we definitely heard the sub with lower tuning clearly having a clear advantage down low. With room gain that would have been amplified so I think that a sub tuned lower will still produce the ULF and have an advantage. I am no expert at this but I know some one like @mthomas47
is running low tuned in multiples in a big open room and getting all the ULF he could want
Originally Posted by indebtbassfreak
Lol, certainly no expert here either. You have been exposed to more subs than i likely ever will so your personal experience holds weight. It goes to show Mike knows what he's doing,, been able to get run out of the room at times if he didn't reduce his volume. 6000^3 on concrete
But if you have seen his equipment (speakers) Wow!! then adding four ULF monsters that we know are properly set up you can see why.
I don't know Mike's settings, but his speakers will pound down below 40Hz so i'm guessing his subs arent tuned to do much above 60Hz leaving even more output for ULF. Man i would love to hear it.
I appreciate the compliment, Joe! I would love to be able to share my audio system with you fellows, and to hear yours in return. Unfortunately, some of the people with whom we might wish to share our audio systems may be located too far away to ever make that possible.
I have fourteen 12" woofers, in large sealed cabinets, for six of the speakers in my audio system. But, four of those speakers still use an 80Hz crossover, and only the ones with four 12" woofers apiece, in 18^3 cabinets, use a 60Hz crossover. Low-tuned ported subwoofers can still wipe the floor with my other speakers, for movies, below about 80Hz.
I definitely think that larger rooms make it more difficult to obtain the same low-frequency SPL and TR that we can get in smaller rooms. But, to me, that simply puts a higher premium on those low-frequencies, and makes our selection of lower-tuned subwoofers all the more important. As you noted, my ULF SPL and TR can literally run me out of the room if I really crank things up with the right movie.
Think of the low-bass this way. If Ray had trouble getting as much low-bass SPL and TR as he wanted with a pair of V1801's in a roughly 2500^3 room (it may have been 2700) then how much harder would it be for those same subwoofers to provide the low-bass he wanted in an even larger space?
I think that the OP has the same dilemma. The V1811's are excellent subs, and they will provide more total mid-bass SPL than the PB4000's will. But, how much total mid-bass SPL is the OP likely to need? For most people, once they can get really good dual subs, they will usually have enough undistorted, uncompressed mid-bass SPL, and mid-bass TR. And now, they can afford to turn their attention to the lower frequencies. As rooms get larger, our listening distances from our subwoofers typically increase, and our room gain starts at lower frequencies. My serious room gain starts at 20Hz, and two of my four subs are 18' from my MLP in my 6000^3 room.
But, as noted above, I think that simply means that I need to put a higher premium on subwoofers with lower tuning points, rather than subwoofers with higher tuning points, if I want to hear and feel movie special effects the way I want to. For a larger room, I think that someone who is primarily watching movies will have sufficient mid-bass from a pair of PB4000's, and a lot more low-bass SPL and TR than he would from a pair of V1811's.
As Ray discovered, the difference isn't in the number of drivers, or even in the size of the drivers. His two V1801's were terrific subs, with terrific mid-bass abilities. But, they drop-off pretty fast below 25Hz. The V3611's are even more powerful, but they have the same tuning point as the V1811's. The real difference for low-bass SPL and TR in movies is in the tuning point. For people who want to maximize the low-bass movie experience, I would recommend a pair of PB4000's rather a pair of V1811's.
So, to answer tswon's original question, I would stay with the PB4000's for a primarily movie experience, in preference to ported PSA subwoofers. Personally, I can't wait until PSA starts to offer some lower-tuned subwoofers. I think it will not only make many loyal PSA owners very happy, it will be good for the audio/HT community as a whole.