Impact of french doors on home theatre..

[chand]

Hi Guru’s,

I am installing a B&W 7 series floor standers and central speaker. Along with 2 KEF sub’s plus 4 atmos speakers. I am refurbishing the whole audio room it has wall on one side and french door on the other. I am uploading a rough sketch (Forgive me sketch), I am now losing sleep on the french door reverb. I am having a big curtain which covers the doors. Hence reaching out to you to get some help:

1. Is there special curtain material we could get to absorb sound, so the sound dont reach the french doors? As i am planning to install some GIK products to catch the Echo’s on the opposite wall.

2. I am planning to install carpets instead of hard wood floor to reduce the sound bouncing off the floor. I cant treat the ceiling because of the atmos. So out of 4 walls, I can treat 3 as one wall is french. Can add the carpet but not the ceiling.

The room is echoing as it is before the installation, so hoping your advise plus some GIK products will help.

I am sure its not ideal, but something is better than nothing. But would appreciate your help and guidance.

Thanks & Regards
Mo

 

[silva741]

The curtains need to be as thick and heavy as possible (and also with many flaps). Search velour curtains. The distance between the fabric and the door/wall is also important, the bigger distance the more efficient the curtains will be.

Having absorber panels on the opposite wall will also help, you need to cover the 1st reflection points. Ideally also on the ceiling, are you sure it's completely impossible to do that?

Your diagram doesn't show where your MLP will be, but the ATMOS speakers location doesn't seem right. Can you make a more accurate diagram?

 

[AndreNewman]

Our cinema room has some similarities, we have two sets of french doors, on the right side and another the back wall as well.

We have heavy floor to ceiling black velvet curtains on almost all walls, you want at least double the curtain width of the wall or door you want to cover to allow for curtain folds, ours are ~2.5 times. Need to plan how much space the curtains take up when pulled back, especially if they are on all walls.

We also have additional acoustic curtains hung on the same hooks behind the velvet curtains, they don't make a huge acoustic difference but it helps to make the main curtains hang neatly and that does affect the acoustics.

I was surprised how much difference the curtains make, it's not as good as 100mm panels at first reflection points but it's definitely worthwhile, can really hear the room change when you close the curtains.

I have some open/closed REW measurements if that's interesting.
I could post some pictures if that's useful too.

These are the curtains we have, you can't buy them I bought all the stock.
Amazon product

These are the secondary backing curtains we have.
Amazon product

For the French doors, they rattled a lot when the subwoofers got going The curtains didn't change that at all. We installed some door drop bars and ran draught proofing tape around the doors and that helps a lot, no more rattles and the bass sounds a bit better too.

If you look for door drop bars, don't buy them from a soundproofing company buy the exact same part from a fire proofing company for 1/3 the price.

We have these ones.

LAS8008 si drop seal

A slimline, face-fixed automatic drop seal with a curved cover plate for enhanced aesthetics. A face-fixed drop seal suitable for upgrading existing doors.

www.lorientuk.com

And yes it's possible to treat the ceiling and have atmos, this will be my next big project for our room.

The atmos speakers usually want to be in a similar location to the acoustic panels (that's how the celing bounce ones work) so you can put panels beside the ceiling speakers or install the speakers inside the panels. You need to remove the insulation material where the speaker is but it's a good way to conceal the ceiling speakers. Dolby HQ have some speakers inside panels like this in one of their atmos demo rooms.

 

[AndreNewman]

Oh and your sketch suggests you plan to sit in the middle of the room. You shouldn't do that, there will always be a huge bass null (a cancellation) in the middle of the room.

Much better to be in the front 1/3 or rear 1/3 of the room and not up against the back wall. Huge sound upgrade just by moving the sofa.