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Hi Sheraz,

I have a few comments and questions...

Acoustic treatment should be done with a plan in mind using in-room measurements to identify SPECIFIC problems so the treatments can be used to treat those problems without overitreating the room. REW's Energy-Time Curve measurment can be used to identify specific reflections, so they can be treated specifically. Austin Jerry's Getting Started with REW, (Pages 78 -84), explains how to run the measurements, interpret them and use the result to apply treatments. (See Attachment and further comments below.)

For an overall strategy for acoustic treatments, it is generally recommended to treat most domestic sized rooms with a combination of absorption, diffusion and bass trapping, as you've done, but not configured quite the way you have done so. Most acousticians recommend staggering absorption and diffusion, and covering not more than 30% to 35% of the room surfaces with treatments. Here is Anthony Grimani, a highly regarded acoustician, describing his use of acoustic treatments:
and
and Bass Traps here:
Each of these videos is over an hour long, but they are chock-full of valuable acoustic information that can help guide you to an optimized treatment plan.

Here's an image of a generalized treatment plan:


Note the alternating use of absorption and diffusion in columns on the side walls.


I can't speak to the issues you had here as I was not in the room at the time. However, I can say that velvet applied directly to the wall should not absorb more than a tiny amount of high frequencies. However, velvet applied loosely to a wall, with an air gap between the velvet and the wall, can indeed absorb high frequencies enough to impact acoustics. Add a bunch of broadband absorption to that, without any diffusion or bare-wall reflections, and it is certainly possible to "over-treat" a room and make it too "dead" sounding.


Clearly you have gone to great lengths to improve the acoustics of your room while considering the light reflectivity of the treatments at the same time. I congratulate you on those efforts!!! Having said that, I have a few comments...

First, the frequency response is not the best measurment to use for evaluating acoustic treatments. The Energy-Time Curve is a much better measurement for that purpose. Instead of depicting Frequency vs. SPL, the ETC shows SPL vs. Time. It shows the effects of the reflected energy and how it decays over time. If you can get an ETC that goes from this:



to this:


...you will have what is considered to be a very good result.
(Note that the Y-Axis is different between these two charts. The top graph is 0 to -50 while the lower graph is +10 to -50. This affects the visual impact of the changes, so view the graphs with that in mind.)

The goal with using the ETC is to reduce the levels of the early reflections, especially those arriving within about 10 to 20 ms. This will allow the ear/brain to more easily determine and delineate the direct sound without the "smearing" effect of those early reflections. Then you also want to maintain and enhance the later arriving and lower level reflections as they add a sense of spaciousness and ambiance. The "enhancement is accomplished with diffusion. The way you've deployed your diffusion, you may not have diminished the early reflections enough to benefit the directivity of the direct sound. Diffusing the first reflection points on the side walls is not always the best strategy. At those points, you want a "Reflection Free Zone" (RFZ), to reduce the impact of those very early reflections. Using "Ray Tracing" (aka the "mirror trick"), and applying absorption at all early reflection points for all 3 front speakers is the generally accepted practice to add an RFZ. Adding diffusion into the RFZ could "enhance" the early reflections, which would not be beneficial. My suggestion would be to take all your absorption and redeploy it into an absorptive RFZ at the first reflection poits of the front speakers, and then redeploy your diffusion on the side walls further back and on the rear wall and ceiling.

Second, diffusers need "space" or "distance" to work properly. The listener needs to be far enough away for the diffusion to "diffuse" enough to be effective. Most 2D and 3D diffusers need 6 feet or more between the diffusers and the listener for the diffusion to work properly, (explained in the videos). I can't judge the distances in your photos, but you should evaluate those distances to ensure your diffusers are appropriately placed far enough away fro the listeners to be effective. Also, if you look at the Grimani diagram above, you'll see that most of the 3D diffusion is placed at the rear of the room, on the back wall, the rear side walls and the rear ceiling. This is intentional, and beneficial.

Third, it is generally not recommended to inter-mingle absorption and diffusion together as you've done. I have never seen your "checkerboard" pattern of absorption alternated with diffusion used before, but I would expect better results by separating the two into and RFZ with individual columns of absorption alternated with diffusion on the side walls and concentrating diffusion on the rear wall and ceiling, (except directly behind the LP, where you want to absorb the direct, first reflection instead of diffusing it.)

I have no doubt that, if your room was too "dead" with your original treatment plan, it is improved with your current treatment plan with the significant amount of diffusion you've added. However, I believe it's possible to improve it even more by deploying your absorption and diffusion differently than you have, and by using the ETC to evaluate and guide your placements.

If you want to use velvet to cover your treatments to reduce light reflectivity, I suggest the following:
  • On acoustic absorption panels, feel free to cover them in velvet because that will not impact the absorption of the panel to a significant degree, and it may actually enhance it slightly.
  • On acoustic diffusers, you can cover your 3D devices with adhered velvet as that will only add a slight amount of absorption to the high frequencies while diffusing the lower treble and midrange, (which is all they're really specified to diffuse anyway.) Unless you want to increase the HF absorption, I don't recommend covering them in loose fitting velvet.
  • If you build or buy 2D quadratic diffusers, or 3D Skyline diffusers, or any other type of diffuser with open spaces, they can either be painted with one of the low reflectivity paints discussed in this thread, or covered with velvet, (knowing that loosely applied velvet will add some HF absorption.) Alternatively, you can cover them in black GOM.
Here are some fairly easy and simple plans to build a 2D quadratic diffuser that you may find interesting and/or useful:


Paint them with low light reflectivity paint and they should have little visual impact while adding useful diffusion. Remember that these are 2D diffusers, so they only diffuse in the plane opposite of their deployment, (i.e., if you place them vertically, they'll diffuse horizontally; if you place them horizontally they'll diffuse vertically.) If you use them on the side or rear walls, place them vertically. If you use them on the ceiling, place them parallel to the seating.

I also suggest you contact one of the acoustic treatment companies that can provide acoustic treatment plans, like GIK Acoustics, Real Traps, or Acoustic Frontiers. They can help you more rigorously and scientifically select and apply acoustic treatments in your room to optimize the response. They also have a vast array of articles on room acoustics and treatments that you may find useful and educational.

Finally, after you've done all the optimization of the acoustic treatments, if you still find the room a little too "dead", you can always use a room correction product that allows you adjust a "target curve" to your response. You can "tilt up" the high frequencies slightly to compensate. This should only be used judiciously and with the guidance of in-room measurements to bring back some of the "liveliness" to the sound. Overboosting the high frequencies can be seriously detrimental to your tweeters!

Good luck!

Craig
Hi Craig,
The room you see now isn't my first implementation. Once I took everything off, I installed 2 panels on side walls covering 1st reflection and also in back corners. I kept it like that for a few months. It was based on absorbing 1st reflection. I have made changes like many many times. I have also used ETC many times. Well familiar with it and read Jerry's guide years back. I have gone thru many iterations in my room and the one I have now has sounded the best. I am no exaggerating when I say that I have changed the acoustic treatments in my room like 30+ times :).
This checker pattern might be something new but the idea is same. Main idea is to absorb/diffuse with keeping a good balance. I don't think that having only Absorber panel followed by Diffuser Panel will work better than having them in 12"x12 pattern. Both will do the same. What won't work is having a large area with absorber or diffuser because that will over absorb or over diffuse. But when used as 12"x12", you are neither over absorbing or over diffusing. Why the pattern then??? Well for one thing, it looks nicer but I have moved these absorbers so many times that their shape don't have sharp edges anymore :). Otherwise they'd look nicer. Oh and here is the checker pattern in Home Theater Of The Month done professionally by Nyal Mellor. 2nd reason of using smaller panels is the flexibility. Have a look at the are area closer to seat. Because of smaller size, I was able to place the way it sounded best. I spent a lot of time in that area because it closer to seats and can impact much strong. My room isn't too big to begin with. Only 12 feet wide. Smaller room are less forgiving. Even small mistake can catch your attention.

You are right that diffusers need space but the one I am using are also referred to as gentle diffusers. I also have 3D diffusers that are much stronger and placing them closer to MLP, I could hear the difference they were bringing and were catching too much of my attention. These gentle diffusers though just disappear in the room and you are surround by a BIG sound stage.

I have watched Girmani's 1st episode and he talked about the same stuff more or less in HT Geek show years ago but in this episodes he made it very clear not to absorb a room more than 15-20% percent. I think Grimani learned what he knows from trial and errors and reading papers. Nyal I think has a different approach. I have spoken to him for his services but I decided to give it a shot myself for fun. Nyal room treatment depents on
1 - Speakers being used in room
2 - How room is behaving based on REW readings.

Using REW readings, he collects all the data and then using speakers make/model, he finds out speaker dispersion patter. Then he puts together the room treatment plan. I have great nothing but great things about him.

As for custom curve, I have been using Dirac for many years so I have that covered.

Now being said all that, you need to drive over here again. I think it should be very interesting to get your opinion. 2 months ago I went to Atmos threater near by and what I loved about the sound in there was the dynamics. It would get louder but never felt over the top or annoying. Specially high frequencies were very engaging. That's exactly what I was looking for and I think I have that now. But getting others opinion would be great. You have heard many systems and your input would be very valuable. Getting my 2nd vaccination shot tomorrow so its safe to come here now :)

Those who don't know, Craig was the very first person who helped me out many years back when I started this hobby. He came over at my place and that was the first time I saw a software being used to measure room. In return, I served him cheese cake and double shot espresso :). BTW Craig, my espresso skills are much better now. I even got a very good machine which I will only show you when you come here :).
Do we have a deal?????
 

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First, thanks to everyone Lon this thread who has posted what they’ve done. Every room and situation is different, so every idea may help someone.

After deciding to add more black to my home theater, I decided on getting a black rug to cover the existing beige wall-to-wall carpet. Not only was this significantly cheaper than getting new carpet ($189 vs $thousands) but for resale value, should a future home buyer not want to use the room as a home theater, it’s easy to roll up the 12’ x 15’ and you’ve got beige carpet below.

I haven’t gotten Royal Black Velvet yet, as I’m waiting for a sale, but to scratch the black itch I picked up black felt. It’s super easy to cut, lightweight and drapes similar to other fabrics. So I put that above and to the sides of my screen for now.

In this picture you can see how much darker the rug is from the black acoustic fabric that is under the screen.
3113812


Here is a shot showing just how bad my beige carpet was, compared to the new area rug.
3113813

And last, a picture from behind the first row of seats.
3113814


Thanks again for everyone’s help.
 

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First, thanks to everyone Lon this thread who has posted what they’ve done. Every room and situation is different, so every idea may help someone.

After deciding to add more black to my home theater, I decided on getting a black rug to cover the existing beige wall-to-wall carpet. Not only was this significantly cheaper than getting new carpet ($189 vs $thousands) but for resale value, should a future home buyer not want to use the room as a home theater, it’s easy to roll up the 12’ x 15’ and you’ve got beige carpet below.

I haven’t gotten Royal Black Velvet yet, as I’m waiting for a sale, but to scratch the black itch I picked up black felt. It’s super easy to cut, lightweight and drapes similar to other fabrics. So I put that above and to the sides of my screen for now.

In this picture you can see how much darker the rug is from the black acoustic fabric that is under the screen.
View attachment 3113812

Here is a shot showing just how bad my beige carpet was, compared to the new area rug.
View attachment 3113813
And last, a picture from behind the first row of seats. View attachment 3113814

Thanks again for everyone’s help.
That is exactly what I did..

Our house sold today and the buyers are not wanting us to do anything to the theater room, so those carpets will be coming with us.
theater room 2.jpg
theater room..jpg
 

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What can you say about this fabric ? Its Microvelvet 9000 and it seems i can only get this at the place where i live ( small town in India )
The fabric is very black and in one picture it is against my wall which is painted flat black and in the other it is against the black carpet in my HT. The slight sheen in the pic on the fabric is due to the camera and not there in person. Its a smooth and thin fabric, so i guess it shouldnt mess up with the acoustics. Cost is around 2$ per metre.

Thank You.
 

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I also wrapped the grid. If not it really stands out.
Also I have a velvet problem... just ordered 32 yards of triple black velvet. Should cover close to the first 11 foot of my room. This is for my new room I’m in the process of building.
I may have missed the finished product but would love to see it once you are finished,
 

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This is with respect to replicating the light source direction and viewing position that you would experience in a home theater. In other words, all the velvet fabrics, which are all directional, are positioned with light sources eminating from in front, washing across the fabric, with you perceiving from the rear; which is essentially what will be happening with projected image, walls/ceiling, and viewing position:



In this regard the WHALEY'S very slightly outperforms the TRIPLE BLACK VELVET, the both of which outperform the FIDELIO


And here's the comparative performances when viewed head on perpendicular, with an additional light source positioned in front:




In this instance, the WHALEY'S very, very slightly outperforms the FIDELIO, the both of which outperform the TRIPLE BLACK VELVET.

ALL of these materials have a sheen, but it is directional, so is typically on visible when viewed from the 'wrong direction'. It is therefore very important to position the fabric in the 'right direction'. The Fidelio is the least prone with respect to a sheen.

Whilst the Triple Black Velvet performs almost as good as the Whaley's when used for side walls and ceilings, it does not perform as good as either the Whaley's or the Fidelio when viewed head on perpendicular, wherein you can see its sheen a bit as well, so personally I would not choose to use it for the front wall, screen frame, or screen masking; where I would use either the Whaley's for Fidelio for this instead. And in fact, due to fact it is least prone with respect to a sheen, and performs almost the same as the Whaley's when viewed perpendicularly head on, I consider the Fidelio the best material of choice for screen frames and non-acoustically transparent screen masking. The Whaley's has good acoustical transparency and is the only of the three fabrics to do so.

The Triple Black Velvet is excellent for side walls and ceilings and I really think that in the darkened environment of a home theater you won't be able to perceive any difference as compared with the Whaley's; but if used for the front wall, screen frame, or screen masking you will :)

Consequently, I rank the performance of these materials with respect to home theater usage as per follows:


SIDE WALLS AND CEILINGS:

1st = WHALEY'S
2nd = TRIPLE BLACK VELVET
3rd = FIDELIO


FRONT WALL:

1st = WHALEY'S
2nd = FIDELIO
3rd = TRIPLE BLACK VELVET


SCREEN FRAME AND NON-ACOUSTICALLY TRANSPARENT MASKING:

1st = FIDELIO
2nd = WHALEY'S
3rd = TRIPLE BLACK VELVET


😉
How does one stick the fabric to the ceiling?
 

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How does one stick the fabric to the ceiling?
I used industrial strength double sided adhesive and applied the fabric to thin panels of plywood then attached to panels to the ceilings and walls. I have a photo walk through of the process in my link below.
 

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I used industrial strength double sided adhesive and applied the fabric to thin panels of plywood then attached to panels to the ceilings and walls. I have a photo walk through of the process in my link below.
I actually did something similar but I used that black foam board stuff, similar to what people use for science projects in grade school. I used a spray adhesive to attach the material to the foam board, creating these black velvet panels, and then hung them on the walls with either small thumb tacks or tiny nails that would disappear into the cloth. The board keeps the material from stretching or looking loose, and I can take the panels down or reattach them as I need to. Also the foam board is a lot lighter/easier to cut into the shapes I need to completely cover the walls and ceiling.
 

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industrial strength double sided adhesive
Thanks; I already have a dark ceiling with 12-in velvet tape strips w/adhesive stuck to the ceiling. But it's not dark enough to my eyes and not as dark as the screen frame. So, thought of doing a second layer with darker material. I'm thinking of simply using Protostar (https://www.fpi-protostar.com/flock.htm); got a sample strip to check it out. Material seems inky dark but it's adhesive seems to be weak. How about if I use an industrial strength double-sided adhesive to stick this Protostar material to the ceiling? Any recommendations for the adhesive?
 

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Thanks; I already have a dark ceiling with 12-in velvet tape strips w/adhesive stuck to the ceiling. But it's not dark enough to my eyes and not as dark as the screen frame. So, thought of doing a second layer with darker material. I'm thinking of simply using Protostar (https://www.fpi-protostar.com/flock.htm); got a sample strip to check it out. Material seems inky dark but it's adhesive seems to be weak. How about if I use an industrial strength double-sided adhesive to stick this Protostar material to the ceiling? Any recommendations for the adhesive?
I thought that stuff is sticky to begin with. Is it not?

I just ordered a sample of this flock:Adhesive Backed Flocked Fabric to cover frames and line drawers

I believe it is cheaper for the amount I’d need and it comes much wider 60” vs 24”.
 

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I actually did something similar but I used that black foam board stuff, similar to what people use for science projects in grade school. I used a spray adhesive to attach the material to the foam board, creating these black velvet panels, and then hung them on the walls with either small thumb tacks or tiny nails that would disappear into the cloth. The board keeps the material from stretching or looking loose, and I can take the panels down or reattach them as I need to. Also the foam board is a lot lighter/easier to cut into the shapes I need to completely cover the walls and ceiling.
That sounds like a good idea. Any pictures of the result?
 

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@craig john , @ARROW-AV , others, great news. I found black velvet that's completely transparent. I did the same test where I stretched the cloth on a panel and then took the reading in REW by placing the panel in front of the mic ~6-8" away. This velvet worked very well. The before and after graph looked exactly the same. Same as if I used a speaker cloth. So this velvet (link below) seems very transparent and I'll be replacing my existing one with this this new one :). Just wanted to let you guys know. If anyone is interested, I can post REW FR to show the readings.

Acoustically Transparent Velvet
 
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@craig john , @ARROW-AV , others, great news. I found black velvet that's completely transparent. I did the same test where I stretched the cloth on a panel and then took the reading in REW by placing the panel in front of the mic ~6-8" away. This velvet worked very well. The before and after graph looked exactly the same. Same as if I used a speaker cloth. So this velvet (link below) seems very transparent and I'll be replacing my existing one with this this new one :). Just wanted to let you guys know. If anyone is interested, I can post REW FR to show the readings.

Acoustically Transparent Velvet
I feel like I've seen something very similar at my local Hobby Lobby and it had a bit more of a sheen/sparkle to it vs the Triple Velvet I have on hand. Do you have any pics of it compared to more traditional velvet?
 

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Let us know how it works out, and how well it works for room blackening. The pic doesn't make it look quite as black as some other velvets, but it's a pic, so it could be misleading.
 

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Harris, how does it compare to your current velvet for blackening the theater?

The cost is great, especially since it’s wider than the other options, but from the image on their website it seems like it reflects back light much more than sy/Joann’s triple black velvet
 

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Here is a picture of the result. My theater has been in nonstop construction for the past year lol I am constantly changing things so room is always a bit of a disaster. I pulled off the panel on the bottom right because I decided to rerun my HDMI through my screen wall because my gear Rack is behind this wall in my office closet, and projector is obviously on the far end of my theatre room. Am tired of replacing HDMI in the attic being a pain in the ass, am going to be hiding the cable behind panels.

Also in the bottom right you can see the wall that isnt covered yet. That is matte black paint, to show how much of a difference the black velvet makes. https://www.amazon.com/gp/product/B00EEJSG90/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1 Is the velvet I used as someone else on here recommended it a long time ago. They tested it vs material that cost 2,3x as much and while its not the same performance it was close enough that the price difference made it a solid choice.

Am still figuring out how I am gonna finish my baseboards/crown molding. Am either going to wrap them in a material (maybe a navy blue velvet to match my couch/acoustic panels) or paint them, but not sure how I am gonna do that yet.
 

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I feel like I've seen something very similar at my local Hobby Lobby and it had a bit more of a sheen/sparkle to it vs the Triple Velvet I have on hand. Do you have any pics of it compared to more traditional velvet?
Let us know how it works out, and how well it works for room blackening. The pic doesn't make it look quite as black as some other velvets, but it's a pic, so it could be misleading.
Harris, how does it compare to your current velvet for blackening the theater?

The cost is great, especially since it’s wider than the other options, but from the image on their website it seems like it reflects back light much more than sy/Joann’s triple black velvet
After placing it right next to tripple black velvet, I could barely see the difference. I have been using tripple black velvet for years and have stepped on it like 1000s of times so not a fair comparison I guess but what I can say is that having both next to each other and all lights off, they don't catch your attention. Now that I have replaced Burlap with this velvet, the difference it brings is amazing. You garra love what velvet does to a projector display :).
 
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After placing it right next to tripple black velvet, I could barely see the difference. I have been using tripple black velvet for years and have stepped on it like 1000s of times so not a fair comparison I guess but what I can say is that having both next to each other and all lights off, they don't catch your attention. Now that I have replaced Burlap with this velvet, the difference it brings is amazing. You garra love what velvet does to a projector display :).
Alright, I might go get a yard from Hobby Lobby and see how it compares. I'd like to use this stuff for my sound absorbers.
 

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Alright, I might go get a yard from Hobby Lobby and see how it compares. I'd like to use this stuff for my sound absorbers.
I think it doesn't matter which one you are using for sound absorber because if the purpose is to absorb, well they all do that. But if you want to reflect, place it on a hard surface and it works great. One point to note is that this is a a stretchy material and is acoustically transparent when I stretch it on the panel. I didn't test it by simply laying it on the panel. Even after stretching it makes the room dark and works great for absorbing light and at the same time letting the sound thru. If you try out material and its not stretchy, it might not be very acoustically transparent. Just something to keep in mind.
 
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