No problem with rotating the room, Beau: Sound doesn't care which way is "up" and which way is "left", so the overall modal response of the room will be the same. You just need to remember which way is which when you use the equations. However, you didn't really turn the room on it's side like that: you turned it on end! Your longest axis is now vertical, but it's usually a good idea to have your speakers firing along the longest axis of the room. So although the modal response will be the same, there are practical reasons why you might want to set that as:
Width: 1= 292meters
Height: 1.14= 332.88meters
Length 1.39= 405.88meters
That would make a nice control room, and still leave about 3m for the live room, which is just about OK for a drum kit.
OK, so it is possible to build and treat a room that is higher than it is long, and that might be an option here, but Daniel will have to think about it: A ceiling 4 m above the ground is pretty high for a control room, and might be a problem from practical point of view (even simple things, like changing a light bulb, become harder that high).
But see below for adjustments, since there are other factors...
Are the "Golden Ratios" (like 1 - 1.14 - 1.39)? Or that 3 or 4 charts that i have, and each one says me one different thing...
Daniel, there are many good ratios, nit just one "best" or "golden" ratio. Smart scientists like Boner, Sepmeyer, Louden and others did lots of research on ratios years ago, and each has his own set of "good" ones. The thing is, if you plot out all those good ones on an X-Y graph, they all lie along a diagonal line, with a few "islands" around it. So you can choose any of the good ones, or even choose ones close to those, and you'll be fine. You don't need to go crazy about ratios. Just stay away from the bad ones, get close to the good ones, and that's it. 1 : 1.14 : 1.39 is Sepmeyer's second-best ratio, if I recall correctly, and that's great.
These existing walls are 15cm brick/concrete.
Great! That's a good outer-leaf. All you need to do to that is to seal the surface, by painting it with something that seals brick/concrete well.
Dimensions above are without any isolation (i think 10cm of isolation at each wall will be good...).
10 cm is the minimum air gap that you want for good isolation. More is better. An air gap of 15cm would be better, and 20 is really good. But that does not consider the thickness of the drywall. 3 layers of 16mm drywall adds about 5cm, so your total wall width (from the inside of the concrete/brick wall to the inside of the room) will be about 20 to 25 cm.
Now, the room-ratio dimensions must be measured on the final inside surface of the room, meaning the surface of the inner leaf that you see when you stand inside the room.
So, that means your maximum room width can only ever be 2.92 -.2 -.2 = 2.52. call it 2.5 m, to make it easy. So that means your dimensions would become:
Width: 1= 2.5 meters
Height: 1.14= 2.85 meters
Length 1.39= 3.475 meters
Once again, you COULD make the room 3.475 high and 2.85 long, to leave more space for the live room, but do you really want a room that is higher than it is long? There are pros and cons....
Will record drums, guitars and voice. Neighbors are a problem, so i need a good isolation. The room is in the 2nd floor.
Second floor is a problem! You are going to need to use lots of HEAVY materials to isolate this room, because "Neighbors are a problem" (so you need lots of isolation), and also "Will record drums". so you need lots of LOW FREQUENCY isolation. That implies mass, and lots of it. You will need a structural engineer to inspect the building and tell you if the floor can handle the huge load that you need to build on top of it. There will be many tons (yes, tons) of materials going into that room: you do not want the floor collapsing under you!
So first do a rough calculation of the weight, considering 3 layers of 15mm drywall all around, (all four walls, plus ceiling), then add in the framing, windows, doors, treatment, and equipment. That total is what you need to give to the structural engineer, and tell him it will all be concentrated around the edges of the room, about 20cm in from the existing walls. If he tells you that it is OK to do that, then we can go ahead with the design. If not, then you will have to figure out how to reinforce the floor enough to handle that.
whoa... with a room that is 7030 meters x 2920 meters, you may want to consider building more than two rooms
Yeah, but don't forget Daniel is from Brazil, and in Latin-speaking countries the comma is used as the decimal point, and the dot is the thousands separator. Confusing!
- Stuart -
