ryan
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Post by ryan on Sept 20, 2017 23:46:45 GMT
   I have a large main room in my house that is my living room and kitchen, 14.5x34 feet with a vaulted ceiling about 12 feet in the center. the room sounds alright but I know it probably needs some absorption on the front wall and probably some diffusion on the back wall. my plan was to build a large frame on the front wall where my screen is projected about 4.5x8 feet and fill it with rock wool to provide what I assume would be adequate absorbtion between the large parallel walls (shortest dimension). I could then remove some if was to much. Im wondering if this will do anything for the low end, if the absorptive material needs to be a Certain depth to address 78hz, would 8 uninterrupted feet of 3 inch material be anymore effective at increasing the range of absorption, than if it were placed into separate columns in the frame with wood separating the pieces of material. is the material depth only relevant as it relates to its distance outward from the wall? would I be better off hiding a giant defuser behind my cloth screen to try to minimize the room modes instead? am I correct in assuming that the valeted ceiling is acoustically advantagus because there is no parallel floor to ceiling issue? or is it concentraiting the sound? the peak is directly between my speakers. the other issue this space has is the early reflection point for the right speaker is much closer (about 5 feet) than the the left which is more like 13 feet. the speakers and screen are placed more or less in the center of the space and can not be moved because the arraignment of the room. I bought stone ledger panels to cover the half wall that separates the kitchen to provide diffusion. the room sounds pretty even when I walk around it, but when seated in the center spot on the couch about 3 feet behind the actual sweet spot theres some tension, also the right speaker sounds louder. I think the room is probably large enough to get away with diffusion for treating the right reflection point. I'm more inclined to use diffusion over absorption wherever possible. I have limited budget and a much more problematic mixing room that also needs to be addressed, so I would like to make some relatively simple improvements to this room, without a bunch of little panels all over the place. it seems like considering the size and shape of the space one large absorption panel or diffusion of some sort that encompasses the screen area should be a good starting point, with a diffuser or a couple of smaller absorption panels behind the couch if needed. I also considered a large plywood piece in the center of the screen with the sides filled with absorption to act as resonating absorber, but it seems like there is a lot more room for error with something like that,I don't want to end up making it worse. any thoughts or suggestions would be greatly appreciated. I tried to included a couple pictures but it said the file is to big |
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Post by Hexspa on Sept 21, 2017 8:35:18 GMT
Hi.
I don't think front wall absorption is the place to start and diffusion isn't the budget option.
From what I understand, vaulted ceilings tend to focus the sound. They also create a new corner.
I'm not seeing what is your intended purpose for the room.
It also sounds like you could benefit by reading the stickies to brush up on general treatment principles.
Thanks.
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Post by Ethan Winer on Sept 23, 2017 19:32:12 GMT
Hex is correct that the front wall is one of the last places to worry about. Then again, any place is good for bass traps. The wall behind you gives the most damaging reflections, though I'd have to see a photo of your large multi-purpose room to give the best advice.
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ryan
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Posts: 10
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Post by ryan on Sept 24, 2017 3:05:40 GMT
  thanks for the input. I added a couple pics, I know there not great. Im having a hard time figuring out the best place to start with this room, I've never had such a large room to work with. Its not for critical listening, Its my home theater and also where I listen to and play music most often. I realize my original post was kind of all over the place. sorry first time posting. I have lots of ideas but no clear starting point. Im just trying to tame the room modes a bit and reduce the reverb time a little, It's just the 2 studio monitors in this room no surrounds. don't expect this to be the ultimate home theater/listing room. Its such a large space that the bass actually doesn't sound to bad. when I turn it up well past the volume most people would mix at Its mostly harsh highs that I hear. Is that more of a reverb time issue than room modes? I wast just curious if a larger panel say 4x3 feet or larger would provide a wider range of absorption than an equal amount of smaller panels of the same thickness. I can't make corner traps because of doors. I have a lot of surface area on the ceiling I could build a couple of large suspended panels. Im going to buy a substantial amount of absorption supplies because I also have a mixing room to treat, and would like to get the most out of what ever I use in the living room so I have plenty left over. thank you very much for your help. Attachments:
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Post by Hexspa on Sept 24, 2017 11:06:14 GMT
I doubt I can help you much. It's such a beautiful room but I'm totally unfamiliar with that kind of layout.
This might be the drugs talking but I think it'd be amazing if you converted your walls and ceiling into bass traps.
What I mean is cut out the drywall and stretch fabric instead of paint.
If you turned that room into a spongy gingerbread house I'm certain it'd accomplish your goals.
Secondly, and I could be wrong and it might be untenable, you might want to consider reorienting the room so you're facing the katanas. My uncertainty lies in the direction of the ceiling's peak. I remember it being said that it would reflect sound back down on you. But if you made it absorptive maybe it'd be alright. I suggest this because it'd give you more symmetry, more length, more places to put absorption and give you better speaker triangulation.
Also, and sorry for being negative Nick, shouldn't your projector screen be lower? I always thought your eyes should be on the top tri fold. If that's true then you could reorient lengthwise, spread your speakers out and possibly sit 38% from the rear wall.
Just some ideas.
Side note: Hey Mr. Winer - when you guys did Doug's control room's ceiling, did you use FRK or none?
Thanks.
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ryan
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Posts: 10
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Post by ryan on Sept 24, 2017 21:36:46 GMT
In a perfect world my screen should be a lower. I put where it is because of speaker hight, they probably should be even higher than they are considering the size of the room, I can't reorient the room this is the only arraignment that allows for a hundred plus inch screen. I was actually thinking about what that would do if there was absorption in the back wall without sheet rock, but Im not going to tear my house apart. It kinda seems like the lowest frequencies that would be creating a room mode are going right through my back wall, its an interior wall Im pretty sure its hollow, and that leads to another good sized room. I should probably get a test mic.
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Post by Hexspa on Sept 25, 2017 0:53:05 GMT
I should probably get a test mic. It's a useful tool. |
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ryan
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Posts: 10
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Post by ryan on Sept 25, 2017 3:47:51 GMT
any suggestions about software for doing room analysis, I've found test mics in the 50-60 dollar range. although I could also buy another pack of rock wool for that. this would be so much more fun with an unlimited budget.
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Post by Hexspa on Sept 25, 2017 12:59:06 GMT
any suggestions about software for doing room analysis, I've found test mics in the 50-60 dollar range. although I could also buy another pack of rock wool for that. this would be so much more fun with an unlimited budget. Room EQ Wizard with an ECM-8000 is all you need. An unlimited budget might be worse! What's better is stretching out your time frame. At least with the mic you'll know where you stand and what improvements your efforts are making. |
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ryan
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Posts: 10
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Post by ryan on Sept 26, 2017 5:11:10 GMT
Im wondering about using the space under my couch for a bass trap, If i remove all of the material in the front from the seat to the floor and the entire back minus the frame and leather. I could fill a floor to wall corner 5 feet wide, 36 inches deep and almost a foot high. plus fill all of the space available behind the back cushion. I could probably fit 20 square feet or more of slightly compressed rock wool in that space. It can't possibly be that easy, could it? It wouldn't exactly make a triangle but It would be a lot of continus absorptive material in a back wall corner. thoughts?
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Post by Hexspa on Sept 26, 2017 19:44:47 GMT
Im wondering about using the space under my couch for a bass trap, If i remove all of the material in the front from the seat to the floor and the entire back minus the frame and leather. I could fill a floor to wall corner 5 feet wide, 36 inches deep and almost a foot high. plus fill all of the space available behind the back cushion. I could probably fit 20 square feet or more of slightly compressed rock wool in that space. It can't possibly be that easy, could it? It wouldn't exactly make a triangle but It would be a lot of continus absorptive material in a back wall corner. thoughts? So you won't tear up the house but (nsfw link to youtube). I have no idea whether that's a good idea. I just wonder how much sound will get in there, not reflected, mids and highs probably won't make it. But, hey, if it's fubar when you're done you can just mail me the pieces  |
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Post by rock on Sept 26, 2017 22:21:55 GMT
I don't see why you can't design absorption into upholstered couches and chairs. I think purpose made from scratch would be better than converting something existing but both should work. Obviously, you need to observe what we know about absorbers like Real Traps and our homemade counter parts and where they are positioned in the room. You also need to understand and have upholstery skills (See youtube). I have looked into this and I find one hurdle to be the covering material. It needs to be acoustically transparent and durable (If you actually want to sit on it).
Placed in the wall/floor corners of the room would seem to me to be the obvious location but anywhere will provide some absorption. In the end, I think testing is key. See Ethan's article about testing rigid fibre glass in an otherwise empty room.
As far a modding an existing couch, that should work to some degree too. Again, to know just how well, testing is the key.
Cheers,
Rock
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ryan
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Posts: 10
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Post by ryan on Sept 27, 2017 19:54:51 GMT
thanks for the input rock, i know a little bit about acoustics, but for everything i know theres probably a thousand things i don't know, so outside opinions are greatly appreciated. Im trying to consider any and all methods of getting adequate absorption or diffusion where I need it, everything from the most budget oriented solutions to the most expensive. In the living room there are no good wall to wall corners that could house a fixed bass trap. If the couch stuffing idea was even half as efeective as a typical approach It might be a good start. If testing showed that it was not drastically uneven. I would be leaving the existing cushioning so the couch would still be usable, or maybe replacing it with acoustic foam. Im sure the leather is reflective, so I thought I might also try putting acoustic foam on the seat and back of the couch and then using a cloth couch cover, and also making pillows stuffed with acoustic foam so the couch could provide a little bit of higher frequency absorption as well. it wouldn't be the only treatment in the room, if it were it might do more harm than good.
alternatively or possibly in addition to that I was also considering making a deep freestanding floor to ceiling bass trap on wheels, with the top section hinged so it would fit through the doorway, that could be moved to the room that Im using.
I'm also thinking about making some rolling absorption panels that can be placed at equal distances from the speakers in an atempt try and address the issue of different distances from the left and right reflection points. If I did that I was thinking a solid backing would probably be preferable to an open panel? and probably at a bit of an angle?
Im also wondering what my target reverb time should be for this space, It seems like most people try to really kill the ambiance as much as possible for a home theater. I also use this room to play acoustic guitar and sing, and the size of this room makes that a more enjoyable experience, so I would like to find a comfortable medium.
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Post by Nigel Spiers on Sept 27, 2017 23:12:05 GMT
Hi,
If it was my room I would look first at the ceiling and place some acoustic panels there. Secondly the back wall behind your mixing position and third use portable light weight acoustic screens (Gobos) around the mixing area. I would not consider bass traps until I had first addressed these areas and assessed results. These 3 steps will definitely yield better and more cost effective results than trying to make a couch or cushions into bass traps.
Good luck with your project
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Post by rock on Sept 28, 2017 17:46:13 GMT
Nigel, I agree your three steps are more effective and better first steps than furniture used as bass traps although if built with typical bass trap materials and placed in corners, they should be comparable to regular panel bass traps...except the the work, time, and material cost  As far as acoustic screens/gobo/rolling panel construction used for reflections, I'd go with 4" un-faced either rigid FG or mineral wool etc. with no solid back. The solid back will tend to reflect low frequencies, left open, LF will pass through. |
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I have a large main room in my house that is my living room and kitchen, 14.5x34 feet with a vaulted ceiling about 12 feet in the center. the room sounds alright but I know it 
