A question about bass and spaces

k-pad

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While burning in a mono speaker in the living room, I noticed something.
There is a 3x3 passage facing the speakers, like an alcove, which has doors on three sides. (Will attach diagram in a later post; this is just a thought)

This is a spot no-one sits at but I do keep going there to use the loo or go to the other room, or the bedroom.

Now, I keep all these three doors closed, and whenever I walked there, the bass there was insufferable.

When I opened one door, it got better. And yesterday, just to try it out, I opened all the three doors and stood there, and voila! The bass was so, so clean. Even the HFs opened up a lot.

Now, this is a spot where no one is ever present.
--

First is the obvious question:
How does leaving this triple door space -- very far (more than 2 metres) away from any listening point -- open, help at listening point?

That the opening up of spaces ought to affect sound at listening point, is kindda obvious. But does it help, or is it a detriment?
--

More to the point, it got me thinking.
Those with small rooms, or in apartments, what happens when they leave the back wall open, if they have an opportunity to do so?

From what I understand:
1. Of course, the room is not pressurised enough for the best bass.
2. But, will this also not eliminate:
a. Room nodes?
b. Standing waves?
c. Bad spots?
d. Nulls?

The reason I ask is, in our community we are always encouraged to keep our spaces enclosed for good bass. But what if a person who does not have enough room, leaves the long side back wall open, and keeps the sub close by the listening position?

Wouldn't they benefit in terms of:
1. First arriving sound is closest to them, and truest, and
2. leaving the back wall open, sending all the long-length bass waves out of the room, thereby not giving the room any reflections on the long wall? (Sidewalls are another thing, but let's not tackle them in this conversation)

Will this not result in clean, but non-pressurised bass at the LP?
Just wondering? Dunno if this has been discussed. Like, could leaving the rear windows open help for those with small rooms?

@Vineethkumar01 @liverpool_for_life @prateekatasniya @Decadent_Spectre
 
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@kpad

I still didn't get the complete picture of the room, but in general from what you are describing it seems like there is a change in the room mode distribution. It is hard to say accurate reasons without seeing measurements or even a modeling of low frequency distribution in room. But this is a possible phenomenon.

Sealed rooms are easier to predict in terms of the modal distribution and hence more easy to 'treat' and get close to intended responses in the low frequency range. Even at higher frequencies, windows and doors, depending on their location impact to some extent by changing the level of reflected sound reaching the listening position.
Also remember that at 100Hz, wavelength is 3.4m at 20Hz it is about 17m.. so 2m is not at all a big distance
 
Not sure I understand but from what I can gather I have seen what you describe, a small alcove where it is almost like a small tunnel with one or multiple doors, the bass peaks here. When you open the door it sort of behaves a little like open air where the bass has room to "flow" and as such the peak is gone or minimized.

Vineeth I think what he is describing is not a traditional square/rectangular room but some sort of small passage way in his living room.
 
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