Planning building a new room

[Rolf]

Hi friends.

For some years I have been thinking of expanding our house. Our house have two floors, and I plan to build the new room with full two ceiling height. The room will be used as both as a living room, as well as the hi-fi and TV room. (With a large screen).

I guess there are several of you that have more knowledge than me about what materials to use, especially on the "slanting"? up to the top.

Some of you can also probably tell me what room resonance I can expect, and maybe a clue on how you think the system will perform in such a room.

When I do this I want to do it right, so suggestions are very appreciated.

Below is 2 (not so good) drawings of what I have in mind.

[Hoerninger]

Rolf,

great idea to plan a room with such a volume, I wish you a big success. :thmbsup:
For clearance, how long is your room from the window to the opposite side? Is the upper floor completely free, there is a line around one triangle shaped window?
Please tell something about the surfaces. For example, is the "existing room" a patio with a lot of glass?
___________
Peter

[Steve Mac]

I would suggest limiting the ceiling size to a degree to control reverberation. It's easier. 9 feet is a great height. 10 is okay. Place a nice carpet down and you will not be disappointed. For a large room if the wall the speakers face is not parallel to the speaker line, this will also help. Generally without going into more detail on exotic room treatment, these basic rules almost always work great. Fabric sofas and chairs... Looks like a fun room! Enjoy!

[Rolf]

For clearance, how long is your room from the window to the opposite side?


The distance is about 7,5 meter. (25ft). Don't know why this did not show on my drawing.



Is the upper floor completely free, there is a line around one triangle shaped window?


The line going from the top and then turn right should not have been there. New program for me. Learning more and more how to use it.



Please tell something about the surfaces. For example, is the "existing room" a patio with a lot of glass?
___________
Peter

This room is not existing yet. The existing room is where our living/hi-fi/TV is today, and is about 27 sq meters. About 4 meters (12ft) of the wall is going to be removed. This will be the opening to the new room, "One step down".

The existing room has 2 windows and an opening at the far right to the kitchen.

Hope this answers your questions.

[Rolf]

I would suggest limiting the ceiling size to a degree to control reverberation. It's easier. 9 feet is a great height. 10 is okay. Place a nice carpet down and you will not be disappointed. For a large room if the wall the speakers face is not parallel to the speaker line, this will also help. Generally without going into more detail on exotic room treatment, these basic rules almost always work great. Fabric sofas and chairs... Looks like a fun room! Enjoy!

Hi.

8ft is the standard height here in Norway, but I wanted to make it much higher, more air and space. Light from above and one normal window to make the fasade look like the rest of the house.

I have been in several houses with high ceilings, and the sound has been great.

I do not want the entire floor covered wit a carpet. The straight up walls (8ft) will probably be the same as in the existing room. From there and up to the top I am not sure what is the best. (For the sound).

[Steve Mac]

Hi.

8ft is the standard height here in Norway, but I wanted to make it much higher, more air and space. Light from above and one normal window to make the fasade look like the rest of the house.

I have been in several houses with high ceilings, and the sound has been great.

8 feet was pretty standard in >25-30 year construction here in the states but newer has been more like 8.5-10...

I don't favor 8 foot ceilings...I've had problems in any room with a ceiling this low. Then again I have a larger system...a smaller system can work just fine there. Rough guess...400-650 sq.ft. sound good with 9' ceilings...then again that's with the system I listen to. There is a break over point in ceiling height that will not sound good in this range depending on floor, wall and furniture treatment though regardless. There are no rules. But some like a room that's a little more alive and others favor a more dead space. I have seen many high ceiling problems that needed acoustical ceiling treatment to counter reverberation. I'm not saying your room needs it, only a word to the wise that hi ceilings can invite acoustical problems.



I do not want the entire floor covered wit a carpet. The straight up walls (8ft) will probably be the same as in the existing room. From there and up to the top I am not sure what is the best. (For the sound).

Some carpeting and hi ceilings...can't really say...could be okay. But what you want is the key and is most important and eventually you can work out any problem so I say go for it! Work out the details later. Good luck!

[Hoerninger]

Rolf, some thoughts:

As far as I have read here you want to listen to stereo recordings and less surround sound if any. So it is practical to follow control rooms guidelines.

Auralex has an example in a paper "Acoustics 101"
http://www.acoustics101.com/common/acoustics101v3_0.pdf
in appendix 2. It is similar to the attached picture.

Some tipps you ca find here:
http://www.acoustics.org/smallrooms.pdf
Do not feel put off, the beginning is too much theoretical for us normal listeners. But there are practical thoughts as well.

A very practical approach Ian has started here: http://www.audioheritage.org/vbulletin/showthread.php?t=16794&page=4

It can easily be seen that early reflections should be avoided and that reflections from behind should be damped or equally distributed. A window straight behind the listening position should be avoided, a wingback chair could be a solution. ;)

A raising ceiling above the speakers is a good start, the falling part of the ceiling may need some dampers or diffusors. A carpet on the floor can be helpful instead. (Some drawings can show where to place.)

The big walls with the tringle top surely need some treatment due to reflections. May be a narrow balcony with some boards, otherwise dampers and diffusors. A wood panelling might be a solution too.

I hope some experienced forumites will jump in. :help:
__________
Peter

[Ian Mackenzie]

I think it depend on Rolf's expectations.

No room is ever going to be perfect and there is no sure way of telling how it will sound until its built. At the end of the day no good advice is going to cheap and if Rolf's wants more specfic information he should perhaps engage the services of an on site acoustic consultant. I imagine building this room will cost a reasonable sum so if one of the key aims is "audio" part of the budget should be allocated to that cause.

I guess what I am saying is don't hold anyone here to any advice, ideas or observations otherwise intended.

[Rolf]

Rolf, some thoughts:


Peter

Hi Peter.

Thanks for the links. This will be much to advanced, and I guess the cost to build such a room is way out of my budget. If I had the money, it would have been really fun. Maybe I will check how much the theoretical cost will be, but I believe there is no company is my area who is willing to do this kind of work. And to hire a company from elsewhere in the country .... $$$+$$$

Remember: It will also be our living room, so furniture placement is a big part too.

[Rolf]

I think it depend on Rolf's expectations.

No room is ever going to be perfect and there is no sure way of telling how it will sound until its built. At the end of the day no good advice is going to cheap and if Rolf's wants more specfic information he should perhaps engage the services of an on site acoustic consultant. I imagine building this room will cost a reasonable sum so if one of the key aims is "audio" part of the budget should be allocated to that cause.

I guess what I am saying is don't hold anyone here to any advice, ideas or observations otherwise intended.

Hi Ian ... Is "HAL" looking at me?

Yes, It would be the best to engage a acoustic consultant, but I do not know of any company in Norway doing this, and I guess if there are some the will charge a lot of $$$, and this is not in my budget. The cost of expanding the house in a "normal" way will be more than enough.

What I understand from the replies in this thread is that my plan of high ceiling is not good regarding sound reproducing. I thought it was the other way, that high ceiling was better than a flat ceiling.

And to all: Yes, my primary idea is 2 channel Hi-Fi, and not surround sound, but I will have that too, when I watch movies.

I have got some ideas, and will post a drawing when done.

[macaroonie]

Here is a thought .... The biggest cost in construction as you know is labour. You might want to investigate SIPS panels as a method. These are a sandwich of board / foam /board and can be used in one pieced sloping roof structures. Ideal for your plan and they have terrific insulation values AND no cavities to resonate. I would expect there will be supply in Norway. The main thing though is that your main structure is up and running in a couple of days.
Here is a link

http://www.tek.kingspan.com/uk/video.htm

[macaroonie]

:) That is a 100mm panel but you can get 150mm also.

[1audiohack]

Hey Rolf;

It is easy to get disscouraged on projects like this as one doesn't know really where the rubber hits the road of reality. There is just too many variables, and choices for us mere mortals.

I just spent three days with Doug Jones who is the Professor of Acoustics at Columbia University IL. His speciality is small room acoustics. We spoke at length about my new project stereo room as well as his instructing me in the art and science of acoustical measurement and data interpretation. We measured everything I could think of and more!

From what I have learned here is the very short of it, symmetry of the room is very important for stereo imaging.

Look at one of the many modal calculators available and use dimmensions that avoid frequency pileups. Your pretty safe to ignore the tangental and oblique modes. The upper frequencies are relatively easy to tame, so get the room all together and furnished before you worry about reflected energy, after all it is living space right?

You only get one chance to get the LF part right, so work to get a good ratio. A high ceiling wont kill you.

Thats the lions share of the worry and it will sound better than most rooms where no one gave any attention to the design, and it won't cost you anything but a little time.

Its hard to know when to stop, and that sometimes keeps us from starting. Draw a line in the sand and get to work!

Best of luck and tell us how you go.

[Ian Mackenzie]

Rolf,

Hal can lip read and he is always watching. So watch your P's and Q's.

Most of the time everything is okay accept when people start being arseholes. Then he can become paranoid which is serious shit for those directly involved.

Back on topic I dont think there is anything wrong with maybe a gable type of roof if you want to create ambience and a feeling of space. You could have some skylights up there as sunlight is perhaps scarce.