False ceiling rattling solution

[xfi]

Hi all, gonna move to new place with dedicated HT room, rough size 6x 5m. Comes with false ceiling of 400mm depth, mainly to conceal pipes and wiring. 
‘I’m a bit worried about rattling and the worse thing to happen is to find that out only when the system has been set up with the ceiling speakers and what not all placed. 
 

I gave a call to ecophon and they recommended this product which they are sure will stop rattling. 
 

https://www.ecophon.com/en/products/modular-ceilings/focus/focus-a/

 

Anyone has any experience with it and any suggestions how to solve the “potential” rattling problem? 

[wechnivag]

Wow, first off congratulations on the new space.  Designing a new HT setup from the very basics (ceiling rattles) is no small task. So many details to attend, from noise control (both inwards and outwards), aircon noise, PJ noise, acoustics etc.. 

 

Coming back to the ceiling rattles, this typically happens with gypsum board false ceilings that have a lot of mass, low resonant frequency and a lot of debris or wiring runs  inside. When excited into resonance, the stuff bounces around and rattles. 

 

The grid ceiling with echophon fiberglass panels are quite low mass system , should not rattle. The echophon panels themselves are good absorbers. To further improve bass damping, you can consider filling the 400mm space with further insulation. 

 

One consideration is if you find a grid ceiling acceptable for domestic use? 

[xfi]

You are absolutely right. Planning for a HT room is even more tedious than the house itself. 
 

Maybe I can go through some of the processes and the ideas that have come up to share. 
 

Noise level. This includes blocking out noise as well as keeping sound in. 
 

Good windows are a prime consideration, and good ones are very effective in keeping unwanted noise in and out. For those with windows already fixed, double glazing can be a solution. There are some companies that offer this solution. Having heavy curtains can also help. 
 

Doors. Maybe I’m lucky cos the room designated has a bit of separation from the rest, so I’ve not gone too much into details yet. Maybe a bit of wait and see. Some of the solutions offered include a STC door that will cost about 4.5 k to install. I’m just waiting to see what kind of nose bleed before deciding. In the meantime, I think I’m gonna install a set of heavy curtains over the door. For one, it gives that cinema feel when going into the room. This will also be effective in blocking sound from going out directly. Also, when anyone opens the door, there is not going to be a sudden explosion of noise coming out but a muffling of sound. In a man cave, it also prevents light from piercing into the room when opening the door. 
 

Walls. In my current place, I have a ngeow neighbor whom I’m sure will hop over to voice displeasure of I play too loud. But in my 10 years of blasting, this has never happened. Maybe they damn tolerant lah. But maybe also cos I built a 6 inch thick wall filled with rock wool and a air gap to stop the noise from reaching their ears. Hey, I don’t want and don’t like this neighbor coming to tell me off

 

 Projector noise. My current one is 2 m away from MLP but I can still hear the difference when it switches from sdr to hdr mode. I’ve always preferred shelf minting rather than ceiling, so for my new place I’m gonna build a long shelf to house the projector. I think the shelf will help shield some noise too. 
 

False ceiling. This is the one giving me a headache now. To me (dunno right or wrong) , the greater the false ceiling depth, the greater the risk for rattling? At 400mm this is more than double my current of 150mm (6 inches). If I stuff with rock wool as done with my current, that’s hell of a lot of rock wool to stuff, and then I’m worried about the weight the false ceiling is bearing for so much rock wool. If I factor in acoustic panels, that’s gonna add more weight. 

The ecophon suggestion was to paste the product onto the false ceiling. I know it can absorb some sound, but low freq? Stop rattling? I can’t afford to test out to find out it doesn’t work. That’ll be a disaster- redo? OMG....

 

 The other option is to tear down the false ceiling and expose pipes and wiring. That’ll also give additional advantage of height which maybe good for atmos? 
Then hang the acoustic panels for sound treatment/ first reflections which will also partially hide the piping. But... I have another problem: there is a beam running asymmetrically across the room which is 350mm
 

One more option: suggested by both my builder and also the acoustics companies. Build a second ceiling over the first. So it’s just like my principle of building a wall stuffed with rock wool to act as a effective sound barrier. More aesthetically pleasing. Can put down lights. Can hang panel and anything you want cos now reinforced. But I lose height! I think height is very impt for atmos? If there is not enough speaker and distance separation, is gonna be difficult to have that panning effect that adds to the enjoyment? This concept came from a show room I visited. Super high ceiling. And then I saw quadratic diffusers on the ceiling some more. Wah , the panning and the kind of sound depth moh tuck teng! Haha then after buying the whole setup you wonder why dun have this effect at home
 

 

[jimi1624705950]

Hi, 

 

I had the same concerns as I wanted to hide a AC cassette in the false ceiling.

 

In the end I went for a sandwich so the ceiling was (from bottom layer to highest layer): gymsum board (the side you can see), rockwool about 4 inch thick, gypsum, then another rock wool. 

 

The rock wool I used had the silver layer removed because it is insulating to heat- just check to see whether yours has it. The product is called Dense Fibre Block and this company gave me a good deal on it so I just went with it: https://www.noisestopsystems.sg/products_infill_dfm_soundproofing_asia_singapore_buy_products.php

 

My ceiling doesn't rattle at all and its made of the same flimsy aluminium strips and gypsum boards like everyone else.

 

ps. you might want to consider putting a bass trap in the ceiling... I didn't end up needing the ones I installed (3m x 1m x 1.5m units). Deep bass resonance used to be difficult to prevent, however if you don't mind using it these days you can probably just EQ the nodes out.

[xfi]

Good to hear from you Jimi. The sandwich solution is good, but I’m concerned about height loss. Pre atmos days, it would be ok, but after audition at this show room, I’m rather convinced that adequate height matters ie as much as possible. Now I’m thinking of tearing down the false ceiling and have hanging acoustic panels as the new “ceiling” (need them anyway, esp for first reflections). Install my first layer of height speakers below the panels, then the VOG speaker above this layer right against the concrete ceiling which is about 500 mm higher. 
 

wonder if that’ll work.....

[xfi]

On 12/5/2020 at 2:57 PM, jimi1624705950 said:

Hi, 

 

I had the same concerns as I wanted to hide a AC cassette in the false ceiling.

 

In the end I went for a sandwich so the ceiling was (from bottom layer to highest layer): gymsum board (the side you can see), rockwool about 4 inch thick, gypsum, then another rock wool. 

 

The rock wool I used had the silver layer removed because it is insulating to heat- just check to see whether yours has it. The product is called Dense Fibre Block and this company gave me a good deal on it so I just went with it: https://www.noisestopsystems.sg/products_infill_dfm_soundproofing_asia_singapore_buy_products.php

 

My ceiling doesn't rattle at all and its made of the same flimsy aluminium strips and gypsum boards like everyone else.

 

ps. you might want to consider putting a bass trap in the ceiling... I didn't end up needing the ones I installed (3m x 1m x 1.5m units). Deep bass resonance used to be difficult to prevent, however if you don't mind using it these days you can probably just EQ the nodes out.

Interesting website. Wonder if anyone tried their acoustic carpets??

[jimi1624705950]

On 12/7/2020 at 12:40 AM, xfi said:

Good to hear from you Jimi. The sandwich solution is good, but I’m concerned about height loss. Pre atmos days, it would be ok, but after audition at this show room, I’m rather convinced that adequate height matters ie as much as possible. Now I’m thinking of tearing down the false ceiling and have hanging acoustic panels as the new “ceiling” (need them anyway, esp for first reflections). Install my first layer of height speakers below the panels, then the VOG speaker above this layer right against the concrete ceiling which is about 500 mm higher. 
 

wonder if that’ll work.....

I'm not sure about height adding to atmos. I would guess that more speakers would be better than more distance/ height for a seamless surround, but I don't know.

 

I wanted a false ceiling at the time to hide my bass traps, and insulate myself from my neighbour (never had a complaint), and have a smooth flat ceiling across the whole house. Found out from a random website recently that apparently a false ceiling also helps reduce the heat in the room as air is an insulator.

[xfi]

I took down the entire false ceiling. To my surprise I thought the room sounded better than before. It sounded more airy and less echoie. Maybe with all the piping and irregular surfaces there is less direct reflection.  Well, this is the first step. 

[xfi]

 My ceiling after removal. Gonna paint everything black, including the air con unit. 

Edited December 14, 2020 by xfi

[jimi1624705950]

16 hours ago, xfi said:

 My ceiling after removal. Gonna paint everything black, including the air con unit. 

A natural diffuser of sorts haha

 

[wechnivag]

Congratulations! High ceilings are good for sound quality.. 

 

 

[wechnivag]

Looks like you may need to do some sound proofing on all the plumbing.... 

 

Water pipes flowing sound can be quite loud.... And you definitely don't want to hear it everytime toilet is flushed?... 

[xfi]

10 minutes ago, wechnivag said:

Looks like you may need to do some sound proofing on all the plumbing.... 

 

Water pipes flowing sound can be quite loud.... And you definitely don't want to hear it everytime toilet is flushed?... 

yep. Gonna wrap the pipes with mass loaded vinyl. There will also be some hanging absorption panels so hopefully enough to shield the water sound. 

[wechnivag]

Awesome. Please share more info on your planned acoustic treatment for the room overall. 

 

Also the gear and setup - AT screen with baffle wall? 

 

What subs are you planning for the room? 

 

I have the same problem with hearing the PJ fan on HDR mode as well. Have you considered a hush box for the projector? That might not be so straightforward, need to ensure sufficient cooling... 

 

 

Edited December 15, 2020 by wechnivag

[xfi]

For room acoustics,  I’m getting professional help for this. I think RA is one area I’ve previously ignored almost totally. All I knew 10 years ago then was some kind of sound insulation, sound reflection like laying a rug (which I actually didn’t do cos my HT was my living room). 

 

Now, I really understand that RA is prob the most important part of the setup. Cos a bad room will make a top speaker sound bad, but a good room can make a mediocre speaker sound good. 
 

Didn’t want to DIY cos first I may not know what I’m doing (not enough experience, and I don’t want to play play then find out it was all wrong and redo, affecting the aesthetics). Second, the treatment of RA by professionals can accommodate both acoustics and aesthetics. Third, the treatment can be measured and tweaked by a trained person. 

 

So I started to do some searching and ended up calling three companies for a quote.  Of the three acoustics company who came, I was most impressed with JD acoustics. Will show some of the results and cont in the next post. 

[xfi]

JD acoustics was the only one who really tested the room acoustics and did a simulation of the effect of room treatment. The idea is to bring down the reverberation time across all freq down to 0.5 or so. This is the recommended RT for HT rooms so a sound/audio room might be different. On the other hand, it is not ideal to have to much absorption as the room might be too “dead”. Low freq are a problem n prob hardest to treat. So bass traps are also a must. 
 

these are the RT times for my room. Quite bad for a start

 

Edited December 16, 2020 by xfi

[Guest francishuang]

1 hour ago, xfi said:

JD acoustics was the only one who really tested the room acoustics and did a simulation of the effect of room treatment. The idea is to bring down the reverberation time across all freq down to 0.5 or so. This is the recommended RT for HT rooms so a sound/audio room might be different. On the other hand, it is not ideal to have to much absorption as the room might be too “dead”. Low freq are a problem n prob hardest to treat. So bass traps are also a must. 
 

these are the RT times for my room. Quite bad for a start

 

The person attending to u? Fuazi? 

[xfi]

38 minutes ago, francishuang said:

The person attending to u? Fuazi? 

Yes, Fauzi.

You also engaged JD acoustics? 

[Guest francishuang]

1 hour ago, xfi said:

Yes, Fauzi.

You also engaged JD acoustics? 

Yes boss, but i did the measurements and choose the items myself. 

I like viacoustic stuff. Simple looks but very effective in the targeted frequency band

Edited December 16, 2020 by francishuang

[Guest wcseow]

36 minutes ago, francishuang said:

Yes boss, but i did the measurements and choose the items myself. 

I like viacoustic stuff. Simple looks but very effective in the targeted frequency band

Hi

Which model did you used?

Thanks

[Guest francishuang]

9 hours ago, wcseow said:

Hi

Which model did you used?

Thanks

Dc2, wavewood and cinema round

For bass traps. I used the psi avaa

Edited December 16, 2020 by francishuang

[wechnivag]

5 hours ago, xfi said:

JD acoustics was the only one who really tested the room acoustics and did a simulation of the effect of room treatment. The idea is to bring down the reverberation time across all freq down to 0.5 or so. This is the recommended RT for HT rooms so a sound/audio room might be different. On the other hand, it is not ideal to have to much absorption as the room might be too “dead”. Low freq are a problem n prob hardest to treat. So bass traps are also a must. 
 

these are the RT times for my room. Quite bad for a start

 

Wow, very thorough job. Thanks for sharing. 

 

It looks like they recommend both the quantity and the type of different acoustic Panel types for different functions? Bass, mid - high, diffusion etc. Do they also include recommendation on placement in the room? 

[xfi]

1 hour ago, wechnivag said:

Wow, very thorough job. Thanks for sharing. 

 

It looks like they recommend both the quantity and the type of different acoustic Panel types for different functions? Bass, mid - high, diffusion etc. Do they also include recommendation on placement in the room? 

Yes they also suggest placement as well. Now they in touch with my ID n electrician for the design

[xfi]

Update: 

things done/to do: 

1. changed door direction. Prev opened inwards which will affect bass traps/ screen placement etc. Had to remove door,  knock down door frame, rebuild door frame then reinstall the door. Don’t wanna think about sound proofing the door or noise block yet... It’s all about the cost. Wait and see how first...

 

2. Will install a curtain btw aircon unit and door frame. Blocks light from coming in when someone opens the door, mufflers sound when someone opens the door. 
 

3. Need to wrap those pipes with vicoustic isoblanket. https://vicoustic.com/product/iso-blanket?iso-blanket=Iso Blanket

 

Down pipes will build a partition around it and wrap with rock wool. 
 

4. Paint the room black. Seriously that was what my ID suggested - including the walls. But will place dark colored absorption panels over the wall on the sides. Was going to paint the front wall black anyway cos of the AT screen. 
Painter will need to spray paint the ceiling / piping / trunking/ aircon unit as well. He says cannot just paint cos it won’t “stick”. So it ends up he’s gonna spray paint the whole room. Dunno how much it’s gonna cost yet
 

5. Wires already laid. Electrician gave one trunking per group ie LCR had one piping so if I wanted to change wiring I could pull through. Hopefully all these piping helps in the diffusion . 

[xfi]

After the wrapping for the pipes. 
But I still do hear the sound of running water yesterday with the sudden downpour. Hopefully when the absorption panels are up it’ll mask the sound.