[goldark]

Now I understand the need for having just 'more' subwoofer for a bigger room to pressurize more space. I also understand that if your room is open to other areas in the house, this space also needs to be taken into account.

However, unless you have a dedicated room that can be closed off, (let's say I have my home theater system in my living room), then wouldn't the volume of the entire house have to be taken into account?

After all, there are inevitably adjoining hallways the lead to pretty much every other room in the house - if we use this definition of open space that needs to be pressurized, then people's subwoofer needs would be mostly astronomical.

Adding one step further to this, say I have a back door open that leads outside - to properly pressurize the room now, you would effectively have to account for 'infinite' space, right? This seems awfully absurd. In this case, how would outdoor concerts ever receive proper bass performance?

Am I looking at this the wrong way?

 

[derrickdj1]

The total size of a room and the ajoining open spaces has a lot to do with the performance of the bass system. Distance of MLP and subs to MLP also has a big factor in the wooferage performance. If the room is large, you will need multiple subs. Vented subs will give you more bang for your bucks.

How large of a room and the other open spaces? I have a 5300 cu ft space and 4 subs are used to pressurize the room for nice LFE.

 

[dsrussell]

Unless you have a fully closed off room, most homes will contain doorways, hallways and various other openings for sound to "escape" (until it too gets reflected). Frequency response from subwoofers can reach 20 Hz and even deeper. The length of a 20 Hz cycle is around 56 feet in all directions (think of it as a point source that radiates outward). In most homes you will get reflections from floors, walls, ceilings, furniture, etc., at far shorter distances than 56 feet (unless you live in a cathedral and have suspended your sub in midair). Sound waves bounce all around you, from floor to ceiling and wall to wall. Each room will reflect sound waves differently depending upon surface textures and composition, and angles (one of the reasons speakers and subs can sound differently in different homes). Sound will travel through open doorways, obviously. And bass doesn't have much of a problem penetrating the average wall. Just walk in another room. The high and mid frequencies will be mitigated to different degrees, and often to the point where one hears mostly the boom boom of the bass frequencies. Luckily most of the sound energy is being reflected back by the walls and ceiling. These reflections can cause nulls and peaks throughout the room, as well as giving impressive bass response in other areas (hopefully at the listening position).

In outside concerts most of the sound isn't reflected, but is coming directly at you (although there will always be some type of reflections going on, be that the stage, the audience or any structures nearby).