Originally Posted by Steve Bruzonsky
As I am renovating/upgrading my dedicated home theatre, I find myself questioning everything so my revamp gives me full satisfaction, without Adam Pelz having to come back repeatedly with me making more changes. HA! (Adam is coming out after my installer gets everything done!).
I currently have and have planned 2 JL Audio f212 subwoofers (2 12" woofers each sub, sealed) and 2 Paradigm Persona subwoofers (6 8" woofers each sub, sealed). Fast, tight, musical subs.
My theatre is 18' 3" wide, 25' long, 12' high!
In terms of square inches, now many inches do I have of planned subwoofers, and as some other AVS Forum members seem to love the 18" subwoofers, how many 18" subwoofers (sealed) do my subwoofers translate to? And how many such 18" subwoofers (sealed) do other AVS Forum member theatre owners have in their theatres to accomplish what they want in terms of bass performance and liftoff?
I use the term liftoff as I found that Wisdom Audio's CEDIA 2019 demo had that, where the bass was musical yet you could feel it under your rump/butt with some nice liftoff!
The area of a circle is π r2 (3.14159 times the radius squared of the circle). Radius is half of the diameter of a circle. JL Audio f212 has 2 12” woofers. 2 x 3.14159 x 6 x 6 = 226.2”
Paradigm Personal has 6 8” woofers. 6 x 3.14159 x 4 x 4 = 301.6”. So my planned subwoofers = 1,055.60”. An 18" woofer, 3.14159 x 9 x 9 = 254.47”. So my planned subwoofers = approximately 4 18” subwoofers.
So How Many and What Subwoofers Do You Have and How's Your Liftoff & Bass? And what's the dimensions of your theatre?
the sense of musicality comes from lots of different things:
1) obviously the ability to move a lot of air with limited distortion. the larger and more numerous subs (efficiency) allows you to achieve very low distortion at "normal" listening levels (where you don't go deaf). I have 8x15" dayton audio based home made subs. I cut the boxes and made these for perfect fit into my walls (hence the 15" and not 18" due to depth).
2) amplification - does not have to be too pricey but you do need a lot for low distortion. Speaker Power for example produces a great deal of excess power where you are NEVER straining the amp. It also has triggers and other stuff to make home theater setup fairly straightforward.
3) The more subs you have, the smoother the total room response up to an approximate 4 subs where it becomes diminishing returns.
4) placement of the subs is largely guided by aesthetics and ergonomics for most people as opposed to acoustic linearity. If anything you want a "peak" sitting right at the 50-70hz range for natural punch and the liftoff feel you are looking for while being flat to the degree that it is possible between 15-50hz. Unless your main speakers achieve this punch based on their placement and your seating position, I would suggest that you have no choice but to crossover your subs higher and fill this gap.
5) using a mini-dsp (4 channel) and doing the Andy C multisubwoofer optimization can be very effective as well.
6) once all that is done, you want to be able to tweak your final target curve to resemble some of the experimentally tested curves like the "harman curve".
The punch region of bass is extremely important to get the best audio for many types of music and for me is even more important that subterranean bass needed for movies (although i like both).
I went so far as doing midbass modules behind the seats to get that extra 50-70hz punch right to the chest and this worked out great. This might not work for most people's space.
Most people think their subs are the problem with their sound... for 99% of people that is not the issue but one of the other factors that they have no idea how to fix... For the average buyer, minimum 2 subs, front corners of the room is probably a good start before going down the rabbit hole. Those of us OCD enough about this nonsense will eventually get the job done by pure force of will. Calling an audio engineer to take care of it might be dramatically cheaper in the long run if you don't want to take your whole lifetime in search of perfect bass...