Originally Posted by Cam Man
This is the first time I've visited this thread. Kinda surprised since I am quite the JBL fan (and a custom dealer, in the interest of disclosure). I've particularly enjoyed your posts on the PT800s and PS1400.
I had the pleasure of meeting and talking with the product engineer for the Performance series and Project Array a few years back. I've recently also rekindled my interest in the PS1400, as I used them in a design I did this year in which I used the Synthesis S4VCs behind the screen.
I did a bit of new research with JBL about this sub, and learned a few things about it. You may already know that the driver is the same as in the Array 1400. Interestingly, the driver came from the pro side while the cabinet design came from consumer. For this reason, it was unfortunately destined from the start to be a marketing bastard child at the company.
The research also took me to the subject that you mention in your comment above. As you mention, the trend in subwoofer design these days is low extention. Curiously, this is where there is very little content in other than special musical recordings. There is very little content down there in film mixes. This low extention is magnified in our home-size rooms by room gain. Although a lot of folks love to feel that low end, it often is an acoustic byproduct rather than content. Accurate? You be the judge. But with 12dB of room gain below 35Hz or so, a lot of that lowest bass is really bloated unless absorbed (virtually impossible in small rooms) or corrected with EQ.
A paradox of most designs that go for the low extension is sound power in the not-so-low range of about 35Hz to 60Hz. This is where the big power in film mixes is located, not to mention kick bass, etc, in music. The PS1400 is specifically designed to have blistering power in this range...at the expense of low extension. The PS1400 rolls off about 12dB per octave below 35Hz specifically to compensate for room gain AND to retain the ability to deliver extreme power between 35 Hz and about 60Hz. The original THX Ultra sub specs required this roll-off for this reason. The newer THX Ultra2 specs changed this to be anechoically flat to 20Hz. Of course, the PS1400 never was submitted for THX certification. It would have conformed to Ultra specs, but not Ultra2 specs.
Near boundary placement of the PS1400, especially corner placement, engages boundary reinforcement which lifts the low end of to near flat at 20Hz without EQ. It gets a free pass to flat @ 20Hz without sacrificing mid-bass power where the mixed content really demands it. Presuming near boundary placement, seating placement, and room proportions are all in harmony, a good room correction utlility like Audyssey (expecially XT32 or the SubEQ) can render superbly smooth acoustic bass response with the PS1400. In the theater I mentioned, I accomplished the final calibration with Audyssey Pro. It sounds fantastic.
We only used two PS1400s, frankly because the shape of the room made it virtually impossible to add two more. Since the room is not a rectangle, we really couldn't go for Todd Welti's nominal four sub configuration.
Anyway, big PS1400 fan here, but not a fanboy. I don't regard any sub as perfect in all situations. The trick with subs is to utilize it properly; right sub choice for the room, application, design and installation/placment with the presumption of achieving reasonably verifiable performance. Put a PS1400 out in a room away from boundaries, and it will sound weak. Do it right, design well, and use good room correction, and it's fearsome.
At least that is my experience with the PS1400. Have you guys found the same or have you found a unique technique that works for you?
I do believe in the PS1400 enough that I scored a superb purchase opportunity of them from JBL and have a bunch available. I'm keeping a few for myself, though.
If anyone is looking, I might be able to provide some holiday happiness if that kind of thing is in your stocking this year.