Pros and Cons of a Listening Room Being a Sealed Box

[NorthStar]

We have better fetishes than making love in front of a roaring fire.

LoL!

 

[DaveC]

Peter, I never thought about things that way until you pointed it out some time ago, but I think you are correct in your observations.

You also talk about the sound energizing the room/hall, something perhaps very much related to the sound filling the room.

Sound filling the room is a good description of what it sounds like, but I think the main factors in achieving it is 1. the ability of the system to resolve fine detail 2. the room acoustics not mangling that information. Neither of those things is especially common...

 

[PeterA]

I agree, Peter. Let me just add a clarification. The sound source still is localized at/behind the speakers, and very precise imaging is still heard, but just like in a concert hall, while the sound is heard as emanating from the source, it fills the acoustic (hall/room).

As you once put it youself, Peter (please correct me if wrong):

Think of a soprano on a stage: the soprano as sound source is rather small compared to the hall, and you hear the dimensions as such, but the sound coming from the soprano voice is large and fills the hall.

Perhaps it's time for me to make a clarification, Al. By "room filling" sound, I mean that the listener in his listening seat has the sense that the room is filled with sound and that he is in the midst of the sound. I do not mean to imply that the sound is the same in all locations in the room, or that if one walks around the room, that same sense exists in all locations. I'm actually not even certain that the entire room is "filled" with sound. It is only the impression that the listener has from his specific listening seat location. I am talking about 2-channel stereo sound and the listening seat location is vital to the speakers/listener/room relationship. This sense of room fill, and also a sense of presence, is best experienced, and most prevalent, in the proper listening location, equidistant from the two speakers.

I suspect different speaker typologies and dispersion patterns have varying effects on this sense of "room fill."

 

[PeterA]

If one has a room which is open on one side to an adjacent space, would it make more sense to locate the speakers in the enclosed portion of the room with the listener in the open section, or would it be better if the speakers are located in the open part of the room with the listener in the enclosed area?

In other words, if the space is shaped somewhat like an "L", should the speakers or the listener be located in the corner of the "L" joining the two spaces? I have always thought it should be the listener in the more open area and the speakers in the more enclosed area so that the sound from the speakers leaves the enclosed and symmetrical portion of the room so that it sounds more balanced.

 

[KlausR.]

Is a completely closed room good because it allows a stereo system to "pressurize" the space?

When there is no sound pressure, then there is no sound, when there is sound, then there is sound pressure. All rooms can be pressurized in the sense that there is sound pressure when a sound source is emtting sound. When at those locations where normally first reflections would originate you have large openings to adjacent rooms then you loose that energy from the total energy arriving at the listening location and your amp has to work a bit harder to obtain the same sound pressure level.

Or can a room with one or more large openings on the side walls be advantageous by allowing excess sound pressure or standing waves to "escape"?

What is excess sound pressure? A room is not a pressure cooker where excess pressure is building up when the lid closed and sealed. Standing waves cannot escape! When having large openings to adjacent rooms you obtain acoustically coupled spaces with a whole new set of issues. Check out my thread on this, and feel free to ask for copies of the docs.

http://www.whatsbestforum.com/showt...coustically-coupled-rooms”&highlight=meissner

Do the answers to these questions depend on the size of the room in question?

No. In concert halls you don't have room modes but the issue of coupled spaces remains.

Klaus

 

[Rodney Gold]

In my sealed room , I also have the "surrounded" by sound thing.. room filling sound with precise imaging and Sound Stage. Often I am surprised to hear things way beyond the sides of the speakers .
I don't believe a sealed room is dead at all , in fact I think its the opposite.. my sealed room before treatments was an echo chamber , far worse than other open plan areas in my house.
I have double doors at the entrance , and when one of the doors (2m x 800mm) is open , the bass and the rest of the sound changes in the listening room

I have helped set up many irregular rooms and rooms with openings to other parts of the house and its really quite difficult to get it all right. Often bass in the room is ok , but if you go to the next area or down interleading passages , its really loud and doof doof...disturbing other house residents

I had a lot of window area in my room , 2 massive sliding doors and a huge corner window ..I replaced them all with glass bricks to emulate the other walls which are brick.

 

[NorthStar]

If one has a room which is open on one side to an adjacent space, would it make more sense to locate the speakers in the enclosed portion of the room with the listener in the open section, or would it be better if the speakers are located in the open part of the room with the listener in the enclosed area?

In other words, if the space is shaped somewhat like an "L", should the speakers or the listener be located in the corner of the "L" joining the two spaces? I have always thought it should be the listener in the more open area and the speakers in the more enclosed area so that the sound from the speakers leaves the enclosed and symmetrical portion of the room so that it sounds more balanced.

• http://www.wilsonaudio.com/pdf/manuals/manual-maxx-series-1.pdf - Section 1.3 - L-shaped rooms (page 16 - 1-6).

 

[KlausR.]

The asymmetry of the walls in L-shaped rooms resists the build-up of standing waves

Utter nonsense!!!

When a sound wave hits a wall you get a reflection, regardless of room shape. This reflected wave interferes with the wave travelling towards the wall, regardless of room shape. The manner in which these two wave trains interfere depends on their phase, regardless of room shape. You cannot rule out the laws of physics, even if your name is Wilson Audio!

What exactly happens in an L-shaped room is described in Meissner's papers

"Examination of the Effect of a Sound Source Location on the Steady-State Response of a Two-Room Coupled System"
"Acoustic energy density distribution and sound intensity vector field inside coupled spaces”

Klaus

 

[Rodney Gold]

I must say , reading that PDF , their concepts of treating a room are a little naive

 

[Al M.]

Sound filling the room is a good description of what it sounds like, but I think the main factors in achieving it is 1. the ability of the system to resolve fine detail 2. the room acoustics not mangling that information. Neither of those things is especially common...

Yes, I have taken great care of my room acoustics by room treatment, see pages 1 and 2 of my system thread, linked in signature.

 

[Al M.]

Perhaps it's time for me to make a clarification, Al. By "room filling" sound, I mean that the listener in his listening seat has the sense that the room is filled with sound and that he is in the midst of the sound. I do not mean to imply that the sound is the same in all locations in the room, or that if one walks around the room, that same sense exists in all locations. I'm actually not even certain that the entire room is "filled" with sound. It is only the impression that the listener has from his specific listening seat location. I am talking about 2-channel stereo sound and the listening seat location is vital to the speakers/listener/room relationship. This sense of room fill, and also a sense of presence, is best experienced, and most prevalent, in the proper listening location, equidistant from the two speakers.

Yes, I agree with that, Peter.

 

[KeithR]

That depends on far too many factors to be able to generalize.

Sure- this entire thread is about generalization because every space is different. I've come around on this after hearing a ton of dealer rooms, folks who have "box in a box" construction, etc. The rooms where I can hear a pin drop often are too dead for my tastes and sound like a recording studio, not a concert hall. I really would love to hear Marty's grand space - and his grand piano

Trust me, I am a believer in room treatment and had a Rives L1 completed in my old condo. But turning my living room into Goodwin's would never be a goal. I have heard several rooms where even just keeping a door open sounds better. Having the back of the room open up to the kitchen wouldn't be a big deal to me, but for some it would be.

If I were doing a dedicated room, I'd use golden ratios, hardwood floors with a rug, and some simple diffusion/absorption. Sound by Singer's backroom (long time ago) was a great example as opposed to its dead-sounding competitor, Innovative Audio.

While I admire some of the work folks do in this direction, I think a lot goes overboard. John Devore has Monkeyhaus sessions at his pad - that's my kind of thing rather than a man cave.

YMMV and all that.

 

[PeterA]

Having the back of the room open up to the kitchen wouldn't be a big deal to me, but for some it would be.

Keith, by back of the room, do you mean where the listening seat is located, or where the speakers are located? Which should be near the opening to the kitchen for best sound, in your opinion?

 

[NorthStar]

Question: A sealed round room...better than a sealed rectangular room?

 

[FrantzM]

Question: A sealed round room...better than a sealed rectangular room?

No

 

[NorthStar]

Ok

 

[sbo6]

Utter nonsense!!!

When a sound wave hits a wall you get a reflection, regardless of room shape. This reflected wave interferes with the wave travelling towards the wall, regardless of room shape. The manner in which these two wave trains interfere depends on their phase, regardless of room shape. You cannot rule out the laws of physics, even if your name is Wilson Audio!

What exactly happens in an L-shaped room is described in Meissner's papers

"Examination of the Effect of a Sound Source Location on the Steady-State Response of a Two-Room Coupled System"
"Acoustic energy density distribution and sound intensity vector field inside coupled spaces”

Klaus

x2 agree. The L cove is almost like its own space creating its own standing wave problems. Also, when discussing an L shaped room, depending on how large is the L is especially relative to your room will be a huge variable.

 

[amirm]

That is some avatar sb!

 

[KlausR.]

Question: A sealed round room...better than a sealed rectangular room?

Have a look here:

https://lra.le.ac.uk/bitstream/2381/1986/3/aiaa.pdf

Klaus

 

[sbo6]

That is some avatar sb!

Thanks Amir! I used it years ago on other forums and decided to bring it back.