I want to buy a subwoofer and I'm interested in ultra-low frequencies, although to be honest, I'm new to subwoofers and so I don't know how concerned with ultra-low-frequencies I *should* be. All that I know is that I want a subwoofer that accurately reproduces all frequencies as low as possible, loudly enough to fill my home theater room, and possibly bigger rooms (for when I move).
My budget: I don't have a set-in-stone budget. However, I'd prefer not to spend more than a few hundred dollars, but I might be willing to increase that if that is required to meet my sound quality preference. I'm sorry that my budget is so fuzzy.
Subwoofer enclosure size limits: I don't really have any enclosure size limits.
Room size: my home theater system is in a room that serves as a home theater room as well as a bedroom. The part that contains my home theater is a near-square, as you can see in the attached picture that shows my TV. It is about 13' by about 13' by about 8'--1,352 square feet--without taking into account the fact that parts of the ceiling are sloped, as you can see in the upper-right corner of the first picture, but that is probably insignificant. The other part contains my bed, which you can see in the second attached picture. In the second picture, you can see the chair that I sit in when I watch TV shows and movies, and you can see in the upper-right corner of the picture that the ceiling is slightly sloped. The third and fourth pictures show my closets, which are inside of the wall that is behind my chair and are facing the bed. They encompass most of the wall behind the chair. They have foldable doors that are supposed to open and close, but I broke off one of the doors, and it doesn't close anymore. I might be able to get it fixed. The ceiling in both closets is sloped, as shown in the last picture. If the acoustics of my closets matters, I can provide more pictures, and if the dimensions of the part of the room containing my bed matters, I can measure the length and width of that part of the room, but I can't measure it's height because the ceiling is a bit more sloped there.
I provided information about the parts of the room behind my chair in case they will impact acoustics.
I've noticed that that the bass from my DCM KX-12 Series Two
speakers--my front-left and front-right speakers--seems to be quieter in my seat than it is in other areas of the room, and possibly quieter than the hallway outside of my room.
Primary uses: I think that the choice of a 'music' sub over a 'home theater' sub (or vice-versa) is a false choice. Ideally, I want a high-quality sub that is great for TV shows, movies, games, and music. I don't know if I can put exact numbers on how much my home theater system gets used for TV shows and movies vs. games vs. music, but more TV shows and movies than games, and perhaps more gaming than music. I don't want to have to choose a sub that is great for one type of content over a sub that is great for a different type of content. I want accurate reproduction of as many of the low frequencies as possible; possibly including sub-audible, though to be honest, I haven't experienced sub-audible frequencies at appreciable volumes, so I don't know what I'm missing. Perhaps you guys can fill me in on what that is like. If I had all frequencies above 0 Hz through 20 khz equalized to output at the same SPL, and was watching Stranger Things or Jurassic Park, playing Rocket League or Minecraft (possibly while music is playing in Spotify), what would that feel and sound like? What about if I, in the future, watch concerts of my favorite musicians?
On the subject of music, which I sometimes listen to in the background while playing Rocket League or Minecraft, I have many, many Spotify playlists, and a few of the ones that I listen to the most are "pop, soul, & R&B", "rock", and "disco & funk". I forgot to mention that one of my other favorite TV shows is Glee; many of the songs in my playlists are songs that were covered on Glee but are in their original versions.
The volume at which I listen to content: I don't understand what the volume level options on my AVR--"absolute" and "relative"--are, but I've set it on "relative", and I set the volume so that I can hear what the actors are saying. So that I can give you a numerical value, I popped my Jurassic Park Blu-ray into my Xbox, went to a dialog-only scene, and increased the volume until the dialog got to a comfortable volume, it got to -17.0 dB. However, my listening volume changes due to my setup's inability to maintain a constant volume across sources. I switched to the Hulu app and started streaming "Late Night With Seth Meyers" and -17.0 dB was too loud for that, so I dropped it down to -20 dB and it's still a little bit too loud, but it's past 11 PM now and I can't continue testing volume levels because it is late and I don’t live alone.
How soon I want to have a subwoofer or subwoofers: I am looking forward to buying and receiving a subwoofer or subwoofers as soon as possible (unless a particular model that I decide that I want will be going on sale during the holiday season, in which case I might wait, depending on how long I'd have to wait).