Fundamental Frequency Calculation
- Thread starter charoo
- Start date
the way
----------------------------------------------------------------------------------------------------------------------------------------------------------------------If you have an irregular room shape or angled walls, you can average the dimensions to get a rough idea of the mode frequencies. That is, if the length wall is angled, making the width 10 feet at one end and 12 feet at the other, you can use 11 as the average for the width dimension.-------------------------------------------------------------------------------------------------------------------------
would it be nice way to calculate that?
----------------------------------------------------------------------------------------------------------------------------------------------------------------------If you have an irregular room shape or angled walls, you can average the dimensions to get a rough idea of the mode frequencies. That is, if the length wall is angled, making the width 10 feet at one end and 12 feet at the other, you can use 11 as the average for the width dimension.-------------------------------------------------------------------------------------------------------------------------
would it be nice way to calculate that?
knightfly
GrouchyOldFartOnBatteries
Charoo, there isn't any easy way to calculate non-parallel walls - the problem is, even if you use an average, the non-parallel condition makes it so that those modal frequencies are NOT as accentuated as they would be if the walls were parallel. This is why some people, including Everest, make comments that it's possibly better to stay parallel and deal with "the devil you know" - Until recently, I agreed but the more I think about it, the more I'm inclined to use splayed walls to eliminate early reflections in the mix position.
As far as I know, the only way to REALLY know what's going on in a room is to BUILD it and MEASURE it. Of course, you do need to have an idea of what you want first, and this is where all the theory and planning come in.
In my next studio, I intend to use designs similar to the ones John Sayers does, concentrating first on outer shell sound PROOFING, then build the inner rooms to the size/shape/juxtaposition I want, but NOT concerning myself with non-internal wall treatment AT ALL, until I've had a chance to put up the music and LISTEN, as well as TEST.
Then, and ONLY then, will I spend any time and money making ANY of the surfaces a specific characteristic. One of the reasons this seems like a practical way to go (for me, anyway) is that I will be doing both 5.1 and 2.1 as well as stereo mixes, so some of the conventional wisdoms will no longer apply (mostly in 5.1 mixing)
I think the best you can hope for is to design a plane-syymetrical space, either splayed or parallel (your choice) based on your own study of the factors involved, and build it ALL like it was going to be a BOAT, and it couldn't leak.
As to wall construction, check out this thread on John's new site if you haven't already...
http://www.homer.com.au/phpBB2/viewtopic.php?t=86
I highly recommend checking out the US Gypsum information - there's an incredible amount of useful stuff there... Steve
As far as I know, the only way to REALLY know what's going on in a room is to BUILD it and MEASURE it. Of course, you do need to have an idea of what you want first, and this is where all the theory and planning come in.
In my next studio, I intend to use designs similar to the ones John Sayers does, concentrating first on outer shell sound PROOFING, then build the inner rooms to the size/shape/juxtaposition I want, but NOT concerning myself with non-internal wall treatment AT ALL, until I've had a chance to put up the music and LISTEN, as well as TEST.
Then, and ONLY then, will I spend any time and money making ANY of the surfaces a specific characteristic. One of the reasons this seems like a practical way to go (for me, anyway) is that I will be doing both 5.1 and 2.1 as well as stereo mixes, so some of the conventional wisdoms will no longer apply (mostly in 5.1 mixing)
I think the best you can hope for is to design a plane-syymetrical space, either splayed or parallel (your choice) based on your own study of the factors involved, and build it ALL like it was going to be a BOAT, and it couldn't leak.
As to wall construction, check out this thread on John's new site if you haven't already...
http://www.homer.com.au/phpBB2/viewtopic.php?t=86
I highly recommend checking out the US Gypsum information - there's an incredible amount of useful stuff there... Steve
knightfly
GrouchyOldFartOnBatteries
Partly. Any mix area should be completely plane symetrical, with the plane passing through the mix person's head front-to-back, vertically. Whatever you have on your left should have its counterpart on your right at the same angle, etc.
The splaying of walls is what helps eliminate early reflections, and yes, they should be splayed symmetrically... Steve
The splaying of walls is what helps eliminate early reflections, and yes, they should be splayed symmetrically... Steve
John Sayers
Solar Power!!
Of course you have charoo - would you care to explain the HR readers that you are currently building a control room and studio to my plan and layout and that we have been exchanging emails about it for over three weeks. And you might mention that it has all been given to you for free.
cheers
john
knightfly
GrouchyOldFartOnBatteries
Charoo, without knowing your math background I'm going to assume none - If I end up "talking down" to you, sorry. It's just the only way I know to (hopefully)make sure you follow...
In geometry, a plane refers to a 2-dimensional group of points, which, if viewed from its edge, have nothing else sticking up. It's sort of like taking a sheet of plywood and looking at it from the edge. You wouldn't be able to see how wide the sheet of plywood was, since you're only seeing the edge.
In fact, let's use the sheet of plywood idea to explain - pretend that you have a thin sheet of plywood passing through your body, in such a way as to have one arm, leg, and half of your head and torso, on each side of the plywood. If you were to look forward, you would see the left side of the plywood with your left eye, and the right side of the plywood with your right eye.
This is referred to as a "median plane" - because it runs down the middle, or median, of your room.
That imaginary sheet of plywood, when you are seated at the mix position, should have the same type/size/shape of objects on one side as it does on the other. This is called, in math, plane symmetry. It means that whatever is on one side of center, has an equal counterpart on the other side.
If you look at one of John's drawings of the control room, you will see that you could draw a line thru the center of the mix person's head, and exactly centered between the left and right speakers, and there will be balance on both sides of that line. This is the median plane I'm talking about. Our theoretical sheet of plywood would follow that line, as if it were stood on edge, balanced on that line.
In order to get a balanced stereo sound field in that room, you would NOT place one speaker closer to the side or back wall than you placed the other speaker, or they would not respond the same and you would lose imaging. Likewise, you would not place one speaker 4 feet off the floor and the other one 5 feet off the floor - that would change their interaction with the floor and ceiling.
I hope that helped, it's been way too long since I studied geometry... Steve
In geometry, a plane refers to a 2-dimensional group of points, which, if viewed from its edge, have nothing else sticking up. It's sort of like taking a sheet of plywood and looking at it from the edge. You wouldn't be able to see how wide the sheet of plywood was, since you're only seeing the edge.
In fact, let's use the sheet of plywood idea to explain - pretend that you have a thin sheet of plywood passing through your body, in such a way as to have one arm, leg, and half of your head and torso, on each side of the plywood. If you were to look forward, you would see the left side of the plywood with your left eye, and the right side of the plywood with your right eye.
This is referred to as a "median plane" - because it runs down the middle, or median, of your room.
That imaginary sheet of plywood, when you are seated at the mix position, should have the same type/size/shape of objects on one side as it does on the other. This is called, in math, plane symmetry. It means that whatever is on one side of center, has an equal counterpart on the other side.
If you look at one of John's drawings of the control room, you will see that you could draw a line thru the center of the mix person's head, and exactly centered between the left and right speakers, and there will be balance on both sides of that line. This is the median plane I'm talking about. Our theoretical sheet of plywood would follow that line, as if it were stood on edge, balanced on that line.
In order to get a balanced stereo sound field in that room, you would NOT place one speaker closer to the side or back wall than you placed the other speaker, or they would not respond the same and you would lose imaging. Likewise, you would not place one speaker 4 feet off the floor and the other one 5 feet off the floor - that would change their interaction with the floor and ceiling.
I hope that helped, it's been way too long since I studied geometry... Steve
small room and fundamental frequency
i have tried to calculate some fudamental frequency of small space and found most of the small space not support very low frequency, but some articles says that it is just a myth that small space dont create low frequency rather we can get very minimal low frequency out of there. dont you think it is a state of confusion?
regards
charoo
i have tried to calculate some fudamental frequency of small space and found most of the small space not support very low frequency, but some articles says that it is just a myth that small space dont create low frequency rather we can get very minimal low frequency out of there. dont you think it is a state of confusion?
regards
charoo
knightfly
GrouchyOldFartOnBatteries
If by "supporting" low frequency you mean a natural sounding reverb, then yes, it takes a larger room to do that.
However, let's say you hook up a 6-string bass to a big bass amp and play the low B string , which is around 30 hZ - if you can do that and not hear anything, then you're welcome to believe that you can't get low bass in small rooms.
The main problem small rooms have, is that the lower modal frequencies are too far apart and so there are more pronounced peaks and dips in the low end response, making it harder to hear just how much bass there really is in the room.
Make sense?
However, let's say you hook up a 6-string bass to a big bass amp and play the low B string , which is around 30 hZ - if you can do that and not hear anything, then you're welcome to believe that you can't get low bass in small rooms.
The main problem small rooms have, is that the lower modal frequencies are too far apart and so there are more pronounced peaks and dips in the low end response, making it harder to hear just how much bass there really is in the room.
Make sense?
knightfly
GrouchyOldFartOnBatteries
Charoo, if John has already designed a studio for you, I don't understand what you need mathematics or room calculations for - you should just find a competent and ACCURATE carpenter, and have him build the studio for you.
Not to get testy, but I've seen questions by you on at least three different sites, and in no case does it sound to me like you're even listening to the answers. It sounds to me more like you're more of a management type that thinks they can ask a few questions, pass on the answers to someone else who isn't knowledgable about building techniques, and end up with a quiet, good-sounding studio.
Trust me, this is NOT going to happen. If you don't want to waste whatever money and resources you have, I would strongly recommend that you find a LOCAL designer if you can, one who is familiar with acoustic design, so that he can oversee every single construction detail.
If not, you will be wasting time, money and materials because this is not an APPROXIMATE science, it is EXACT in many ways.
Just one example - let's say you build a wall that, according to the STC charts on the SAE site, has an STC rating of 60. If you leave a crack that is maybe 1.5mm by about 3 meters long ANYWHERE in the construction, you will be lucky to get STC 40 performance.
Also, even if you build everything PERFECT, but use anything but Acoustic-rated, non-hardening, non-shrinking caulk, then 6 months to a year from now your STC 60 wall will DEGRADE to STC-40, just because it is no longer properly caulked and will have cracks for the sound to escape from.
There are hundreds of little details like this, any one of which can cause a design to fail.
I sincerely think that maybe you've bitten off more than you can chew here - I hope that, since this seems to be somewhat of a charitable project, you can find some local professionals who would be willing to donate some of their time - otherwise, I will be amazed if you are happy with the results.
I'm sorry to sound so negative, but I really believe the above comments to be true... Steve
Not to get testy, but I've seen questions by you on at least three different sites, and in no case does it sound to me like you're even listening to the answers. It sounds to me more like you're more of a management type that thinks they can ask a few questions, pass on the answers to someone else who isn't knowledgable about building techniques, and end up with a quiet, good-sounding studio.
Trust me, this is NOT going to happen. If you don't want to waste whatever money and resources you have, I would strongly recommend that you find a LOCAL designer if you can, one who is familiar with acoustic design, so that he can oversee every single construction detail.
If not, you will be wasting time, money and materials because this is not an APPROXIMATE science, it is EXACT in many ways.
Just one example - let's say you build a wall that, according to the STC charts on the SAE site, has an STC rating of 60. If you leave a crack that is maybe 1.5mm by about 3 meters long ANYWHERE in the construction, you will be lucky to get STC 40 performance.
Also, even if you build everything PERFECT, but use anything but Acoustic-rated, non-hardening, non-shrinking caulk, then 6 months to a year from now your STC 60 wall will DEGRADE to STC-40, just because it is no longer properly caulked and will have cracks for the sound to escape from.
There are hundreds of little details like this, any one of which can cause a design to fail.
I sincerely think that maybe you've bitten off more than you can chew here - I hope that, since this seems to be somewhat of a charitable project, you can find some local professionals who would be willing to donate some of their time - otherwise, I will be amazed if you are happy with the results.
I'm sorry to sound so negative, but I really believe the above comments to be true... Steve
hey
well its' not that i am not trusting people or something but in spare time learning things is not tha bad...... although i am designing my according johns layout and he is giving great support infact all the people are doing great..... i am just a aspirant to learn more and more......well i am listening everyone and learning a bit...i am not doing this for myself nor i wanna make any profit with this project ...... i am just boiling myself bcz i want to help this cause... otherwiz a 23 yrd old guy have lots' of things to do on weekends.......
regards
charoo
well its' not that i am not trusting people or something but in spare time learning things is not tha bad...... although i am designing my according johns layout and he is giving great support infact all the people are doing great..... i am just a aspirant to learn more and more......well i am listening everyone and learning a bit...i am not doing this for myself nor i wanna make any profit with this project ...... i am just boiling myself bcz i want to help this cause... otherwiz a 23 yrd old guy have lots' of things to do on weekends.......
regards
charoo
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