Acoustic Baffles and clouds are available in the market, you could check that for ceiling.
Need opinions on ceiling reflections
All,I have a soffit that is running length-wise on the LEFT side of the ceiling (picture in my system). The ceiling is 8' and the soffit part drops down about 1'. The speakers and sound panels are positioned with a precision of 1/8th of an inch and it sounds amazing - especially on the RIGHT side. The music appears to come from way back and way outside the RIGHT speaker and you can actually "look" that images of various instruments playing in those empty spaces. But I have a heard time "seeing" those images on the LEFT side speaker. I have a feeling that this issue happens because the reflection point on the left side ceiling is a foot lower than the one on the right side ceiling. I was planning of getting some acoustic foam and attach it to the ceiling using T-pins (since it is a textured ceiling and foam tapes will not work). I assumed that this will absorb the reflections and could work on restoring the proper timing/clarity on left side.
Could you guys weigh in and let me know your thoughts? Please feel free to let me know if I am off and the issue is completely different.
Could you guys weigh in and let me know your thoughts? Please feel free to let me know if I am off and the issue is completely different.
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As the OP, I wanted to get back on the solution that I put in place. And I still continue to learn more about acoustics.So I went with the GIK 242 2’ X 2’ panel that I mounted, flush with the ceiling. I used a "corner bracket" to do this. My initial position caused minor improvement. The music from the left speaker now were much more cleaner. So I asked my son to hold the mirror against the ceiling panel and I found that the mirror image of the tweeter was off by a couple of inches. Hence I moved the panel about 4-5 inches, but now part of the panel was not under the soffit. And this is where the music transformed and now the images were coming from the left side of the left speaker just as the right side images. I have the new panel pic on my system page so you can see how I mounted it. And at this point it stuck me as to why, when I had my absorption panels on the 2nd reflection point a couple of years ago, the music lost all dynamism, to the point that I had to move the panels to the back wall. So the soffit was causing "part" of the sound waves to bounce off the sides of the soffit and then hitting the second panel. So most of the music was getting absorbed and that was causing a "blank" at my listening position. With the new panel in place, the sound now hits the panel and appropriately travels at the listening position. I am glad that it was a learning experience, and think that there is a lot that can be done with proper room treatment. But there is no end to that. I have achieved what I was looking for and it is amazing to hear the same music which seems so much more coherent and engaging. Thank You to all who responded to my post 🙏🏼 |
Bass response! doing so effective makes a say a 4inch panel 8" . Here are a few links to explain further and a few installation options as well. http://https//www.youtube.com/watch?v=dUEnUuKZ1ZU http://https//www.youtube.com/watch?v=zjldCltb3XI |
@milpai - I don’t know if this will help, but here are details of my current room.... It is much like your own, but with two dropped (sofit) sections and a beam that run cross the room, as opposed to the length of the room as in your case .The room is also "L" shaped, with the longest wall being 42 ft and the area where the audio system resides is 17 ft wide Both speakers are located 8 ft from the wall, which places them under one of the dropped sections, so there is very little sound behind the speakers and what sound there may be is probably trapped by the dropped section. In front of the speakers is a beam and then a second dropped ceiling section is located behind the listening position, which I believe is mitigating ceiling level reflections from the wall at the far end behind the listening position. My speakers are rear ported, but the ports are 2" x 8", so there is very little in the way of pressure waves and the internal bracing is designed to minimize standing waves. Also the room is fully carpeted, so I have no bass related issues either When I first setup the system in the new room I was amazed that the only "treatments" it required, was to handle side wall reflections, so I believe the dropped sections are acting in a similar manner to the vinyl blind that I had installed in the last room and they prevent/trap ceiling reflections Initially, I did have a couple of traps in the corners, but even those proved to be unnecessary, so I have removed them also. Another room where I found the vinyl was particularly helpful was in a friends 12 foot high apartment with hardwood floors, concrete walls and ceilings. Once again the vinyl only had to hang down 18" from the ceiling. The improvements were immediately noticeable. In a couple of audio stores I frequented, the ceiling are quite high, so they had various traps and dispersion devices hanging close too the ceiling. I have read corners at the ceiling/wall boundary can be an issue, so installing some sort of crown molding may prove beneficial Hope that helps - Regards - Steve . |
@milpai - One thing I have tried tried worked very well in a couple of very different rooms is a vinyl blind behind the listening position. It is fastened at ceiling height an extends down between 15"-18" You could simply use a piece of vinyl and pin it too the wall behind the listening chair each side of the dropped ceiling section The best vinyl can be acquired from those companies that make signs - it is about 1mm thick and very flexible. I used a vinyl blind because I thought the window that was behind my listening position was the issue, but after it was installed I realized it was not the window, but the reflections at the ceiling causing my problems Regards |
One interesting mounting I found on ATS site was the Rotofast mounting system. This really can get the panels flush against the ceiling. I am not sure if I have studs in that soffit, as I understand that it was created to hide the iron beam (this room is in the basement). Wonder if the Rotofast will work with just the dry wall mount. |
@onhwy61 Not test CDs, but regular CDs. For example: 1. Five Feet High and Rising - Johnny Cash 2. The House Song - Peter Paul and Mary 3. You never Give Me Money - Beatles 4. By Myself - Rosemary Clooney 4. Sweet Lullaby - Deep Forest On the Deep Forest sounds seem off the panel at the first reflection point on BOTH sides. These are some (few examples) of the songs that make you sit up and gawk at the sound stage. Honestly that is ear candy to me and it thrills me up to listen to more music. But that is what I am looking for in other songs. Newer recordings seem better in this regards. But somehow (maybe I a hallucinating) the LEFT side the sound seems to stick closer to the speakers and not as much outside as the RIGHT side. Maybe I am being finicky - but I think I should at least give it a try. Thank You everyone for the excellent feedback and sharing your experiences. I have got responses from GIK and ATS. Will take it up further. Really appreciate it. |
I’ve recently started using Caruso ISO-Bond. Tough to find in the US, but to me it is worth it. I have psoriasis, working with Rockwool & Fiberglass is not fun. I do have 8” thick rockwool BB absorbers that I built years ago that I still use, but these days I only use ISO-Bond. Good luck on your journey, acoustics make such a large improvement. |
@milpai Very nice system and room. I am all about symmetry, so in that vein I would equalize the soffit such that it is centered. Yes it looks like that would double its width. But unless you always listen with eyes closed that visual imbalance will be hard for your brain to ignore. I predict that no matter how much acoustic treatment you use the imbalance will remain. I apologize that this may hurt more than help. Regards, barts |
@milpai Possibly of interest: https://www.soundonsound.com/techniques/diy-acoustic-treatment-15-minute-challenge |
I would get 10 - 15 5 foot artificial ficus trees and 2 to 4 7 - 8 foot artificial ficus, as leafy as possible. I would position two tall trees and enough small one behind the speakers to "hide" the green wall and a tree in front of the wood panel (projection screen?) that can be moved out of the way when necessary. I would also place two ficus trees(tall ones, preferably) in each corner in front of the corner reflectors. I would place one tree behind and slightly to the room center line of each speakers. I would place one tree between the speakers and the wall absorbers to enhance diffusion of side wall reflections), one tree to each side and slightly in front of the primary listening position. I would place at least four trees along the back wall and along the rear side walls. Maybe two a couple of feet behind the listening position. Yeah, your room is going to look like you're on a hunting trip, but all those artificial ficus trees with their leaves act like diffusers. And they work great. So your question is what to do about ceiling reflections. I suggest that you need to handle general room reflections first. What you have appears to me to be inadequate. |
Very good point indeed. But I don't drive with window rolled down. The vocals are dead center. The songs don't appear left heavy. I think there is some smearing going on on the left side. The images appear pretty close to the left speaker. I want them coming off at least 2 feet to the left and 4-5 feet behind the left speaker, just like how the right speaker images. The images in the middle appear close to the wall behind which is almost 6 feet away. |
Fiberglass is a nuisance. It has to be covered correctly or glass fibers get into the air and some of us, like me, get itchy just looking at the stuff. Acoustic foam is every bit as effective down to 250 Hz and eons easier to use and in the end cheaper. It is also easier to specify for a certain situation in terms of thickness and profile. Now unless you are lucky and able to have a room in your house that does not have parallel walls the single best way to deal with parallel walls floors and ceilings is to have speakers that do not send sound in their direction. Then if you are really clever you make your room without a rear wall and you don't have to worry about that either. You can leave your side walls and ceiling live for ambience and if you have speakers like mine or any other dipole just a little absorption behind the speaker using foam or fiberglass, if it does not make you itch completes the picture. |
@bigby Thanks. I did take a look at you room. You have amazing room treatments and that room looks pretty nice and big. Those ceiling treatments probably do wonders. But I am looking at something simpler. I also use GIK throughout my room. But I don't think they would sell a single panel. Nevertheless, let me reach out to them with my requirements. |
Nice system and room setup. I used 3 GIK panels on the ceiling. They were purchased some time ago. See them here. The two outer panels are 100% absorption for 1st reflection points. The center panel has absorption/diffusion. They are suspended using eye hooks and wire. They were recommended by GIK. You may ask them for a solution. You could make the soffit symmetrical down the center of the room, but that is a lot work. |
Diffusion and absorbtion, isn't that what we're after? I've been interested in BAD (binary amplitude diffusors) panels for a bit of both for my room. There are some gurus at it in the forum, judging from many system pages I've seen. All those who take the time to post your system pages, more often than not, you are inspirational to me. 👍 |
@mijostyn I should clarify. I, me, would not use foam -- I am talking about the cheap stuff, not the OC 703 etc. For reference, one might scan for the word "foam" here: https://ethanwiner.com/acoustics.html |
hilde45, why would you avoid foam? It is inexpensive, you can order it with all kinds of profiles and depths. I use 4" acoustic foam tiles. It has a nice sparkle to it and you can alternate the direction of the grooves creating a nice pattern. It works as well or better than anything else I have tried. The only down side is that it is cheap and people think you have to spend a lot more money to get something that works. Anechoic chambers are made with acoustic foam. I have never seen audiophile acoustic anything used in an anechoic chamber. I can hear it coming, "that's not the same as treating a room." Heck, it sure is. You just would not use as much. Effective sound absorption is just that. You always have a choice as to how much you use. Another advantage for the OP is that it is very light so tacking it to the ceiling is easy. |
Following are links to spec's for each (scroll down) and then a discussion of such... https://www.atsacoustics.com/page--Selecting-the-Right-Acoustic-Material--ac.html https://gearspace.com/board/bass-traps-acoustic-panels-foam-etc/670883-knauf-product-equivalent-oc70... DeKay |
@milpai My wife sewed a pillowcase for a panel with a good acoustically-friendly fabric. It fits tightly but there is a bit of slack. I stapled it to the ceiling. There are mounting brackets and nicer ways to do things, but since I needed to see if it would work and how it would sound, I started in with a prototype-first mindset. |
Gentlemen, Thank You for the various suggestions. I will start looking into getting the Owens Corning 703. Thinking of 2' X 2' X 2". @noromance the idea of symmetry is nice. But like I said, the RIGHT side has absolutely no issue. So I don't want to touch something that is working fine.😀 @mijostyn currently I have no plans to change the speakers. @hild45, I had taken a look at ATS site yesterday. And I see that you have their OC 703 panel. What did you use on the one panel that is flush mounted on the ceiling? |
I would avoid foam. I bought OC 703 and covered in fabric to see how it would help. My ceilings are 6.5' so it helped a lot. Couple thoughts on your situation: Visual symmetry and audio symmetry will differ. Be bold about experimenting with asymmetrical placement and toe in. Try getting a sense of reflection differences with a calibrated string. Using this method, you will learn where the most damaging reflections are happening and this can guide both speaker placement and treatment placement. The crucial reflections are from about 4-10 ms or so, depending on your room's dimensions. Conquer them and your soundstage imaging will be made more definite and appropriately located. Buy a measurement mic and download REW. Measure each side (L and R) independently. Look not just at frequency results but at the impulse responses. You should be able to see the differences in the room reflections. This is involved but doable and very effective. What you teach yourself will be useful for the future. |
All you have to do is treat the ceiling with foam acoustic tile in a symmetrical fashion. Very inexpensive. Go to thefoamfactory and check out prices. Another way to deal with the problem is get speakers that do not send sound up, horns and line source speakers. Speakers like Magnepans and ESL do not send sound up or down and require much less work with the room, just some deadening directly behind the speaker. |
Experiment with a few sheets of the 703.It's light enough to hang from screw eyes with heavy twine from the ceiling joists.If you find it's effective, make or buy something more attractive.I had as many as five 2' x4' panels on my ceiling but ended up with only one positioned exactly between the speakers and my listening position. I thought I would have to spackle all of the tiny holes but I can't see them at all which made me happy:-) |
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@noromance , @asctim, Thanks. The panels on the back are a bit thick (GIK 244) and mounting would be a pain. Any suggestion on where to get a square 2' X 2' X 2" thick panel? How do you mount such a panel on the ceiling? What about handling this stuff? Current GIK panels are all finished products, so handling is not an issue. |
That's a great looking room! I think you are probably right about that earlier ceiling bounce on the left having a noticeable effect. Fiberglass as noromance suggested is more effective. 2" thick Owens Corning 703 should be enough to test it out. It might work best to treat both the duct reflection point and the right side ceiling as well to keep it symmetrical. |
I was planning of getting some acoustic foam and attach it to the ceiling using T-pins (since it is a textured ceiling and foam tapes will not work). I assumed that this will absorb the reflections and could work on restoring the proper timing/clarity on left side.Don't use this stuff; it sounds bad - dry and grainy. Look at Owens Corning 703. |