# Need help with flutter echo problem



## Eric Window (Sep 17, 2015)

I need advise with a flutter echo problem in the home theater I built in my basement. It is a 13' 4" wide x 14' 7" deep x 9' 2" tall room. There is a 1' high by 4' deep raised floor in the rear of the room. Floor is padded and carpeted and ceiling has acoustic ceiling tiles over a drywall ceiling using a CeilingMax grid system. Walls are drywall except one wall with Quietrock wall panels and a solid exterior door. Furniture includes 3 plush leather recliners in the middle of the room 5' from the screen and a 7' plush leather couch on the rear platform. I have a 7.1 speaker setup with 3 floor and the rest wall mounted. All AV equipment except the projector is in a separate closet located outside the room and uses an IR repeater system. The door is located 4' from the rear wall.

My problem is I get a significant flutter echo in the front 7' of the room. It is most noticeable when the system is off when I clap. My sound sounds pretty good but I am sure it could sound much better if I deal with this echo. I tried a couple of 2x2 acoustic absorbing panels with zero results. I am not sure what to do and really don't want a trial and error fix since acoustic treatments are expensive. I also tried a local high end theater store for advice, but what they told me to do (upper corner absorbers) did not work either. Thanks for any help anyone can give.


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## bpape (Sep 14, 2006)

Generally flutter is generated high on the walls. I would use some panels horizontally from say 7-9' off the floor in the front half of the room.

But understand that clapping doesn't really replicate what you listen to as when you do, the source of the sound and your ears are in the same place which is not how you listen. Especially when you stand in the front 1/2 of the room which is likely not where you're seated. What happens if you clap at your chair?


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## Lumen (May 17, 2014)

And you can also have someone stand at the sound source(s) and clap, while you sit in the LP. Stay seated. No cheating! :R


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