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Recording in Rooms with Echo's


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I'll be recording a feature later this month and have been part of the location rec's.

So far all of the places that we have seen have a considerable echo (they are usually large, brick or stone basements) and it's looking like it'll be one of them.


Currently my dealing with these large brick rooms will be to put blacks and sound blankets on the floor and as many on the walls as possible.

And when we shoot mid or tight to bring a sound blanket curtain towards the actors.

I have already stated to the producer that for wides they may have to use wilds or audio from other takes (which they are fine with).


My question to you all is how best to deal with these types of rooms?


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Seems like you are prepared to do a lot of the right things  ---  treating the space is definitely the right approach though it is often the hardest to accomplish (when there is little or no cooperation from production, camera, production designer, and of course the  time factor). Hanging furniture pads (whatever you want to call them  --  sound blankets) can be very effective but it should be done properly. Hanging pads flat against a wall is much less effective than hanging the pads a few inches away from the wall (providing some air space). Hanging pads overhead (ceiling) is harder to do but if they are hung not flat but coved (like waves) they are much more effective. Maybe some others will chime in with some of the methods they have used in the past for treating rooms.

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Whatever I can get away with.  Since the OP is working on a feature I'm hoping there are some meetings and scouts etc so that requests to the Art Dept etc can be made and production knows that the reflective rooms will be a sound issue.  That said--the empty look of those rooms may be exactly why they were chosen, and production may have the usual "lav 'em all and push the problem to post" attitude.  It really depends on how sound-oriented the director, producer and even DP are.  If they came from commercials or music videos etc, then I would expect more or less no mercy.  If they are from indie drama or even theatre then they might be more supportive.  Hence the need for serious meetings and probing questions.

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If you run out of absorbers, try diffusing the slap between parallel walls. Anything that'll aim it in different directions - like round fiber tripod cases against the wall, or even PAs and others leaning against the wall - will help. Not as much as absorbers, but every bit counts.


The other thing, of course, is inverse-square. The closer the mic is to the actor's mouth, the less reverb by comparison. Earsets or hair mics can be very helpful... if production is willing to cooperate. I'd rather add verb and ambience to something that's too dry when we get to post, than try to get rid of big-room reverb in an intimate close-up.


(I'm waiting for some plug-in company to invent a Neural Network reverb-killer, rather than the algorithmic expander-oriented ones we have now. But I can't figure out how they'd ever derive a useful training set. Polluting dry recordings with artificial reverb would just train the NN to reject that artificial reverb, not the incredibly complex early reflections of the real world. )

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I've suggested this on the forum before but I'm not sure anyone has taken the idea and run with it. It is a bit expensive (the reason I never actively pursued it myself) but it seems promising.


Auralex Acoustics make a sound absorbing cylinder called a LENRD. It's designed to be stand mounted and could readily be moved anywhere in a room where it might be effective. One could easily use a rolling stand to facilitate rapid deployment.


However, each LENRD costs about $672 and I expect you'd need at least two, maybe three, to really make a difference. If you have the funds, I think it would be worth a try.


Link to the Aurelex LENRD:



They also have other sound baffles that make a low wall or other acoustic "chicane."





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What a great community this is. 

I would  suggest if allowed by the shot is to place a soft surface under the talent and point  the mic at it. It is a negative fill for audio and it really does help reduce the reflected sound, and it really does help.  I did 2 movies where most of the dialog was in a school bus being towed on a 40ft trailer. One Production Designer loved the idea of covering the entire floor in a short industrial carpet, the other wasn't interested and left the linoleum. One movie was easy to mix and the other was not so easy and didn't come out as well. It is the reflections that make a room sound echoey and when you can reduce them it will all sound better.



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When I first started out we were doing a press day when Tori Amos founded RAINN organization and there were crews setting up for interviews in a few rooms in an old building in East Village, NYC. wooden floors and hard walls.  One crew had treated their entire room (maybe 10x16 feet) with soundblankets on the floors only and when I walked past it it still sounded full of echo. So yes blankets hung vertically help a lot more.


On a movie I dayplayed for another mixer we were in a large room.

The boom op helped me use furniture blankets on C-stands vertically in a V-formation spaced about every 10 feet back from our area. It was the first time I had done it but he told me his regular mixer did it that way. I think we used maybe 6 C-stands. It did help somewhat.


On a short film in a bathroom with one character standing in front of the sink talking to himself in the mirror with CU shots only I put blankets out of the shot in the bathtub and under the toilet and they made a huge difference. It is like when you go into a new home and there is an empty bathroom without a shower curtain. Here is Excerpt from Sam’s Tail, a branded comedy for Heineken. scene starts at 2:25



I need to get some furniture blankets. Maybe start with a few.

I heard on a youtube video that some people can buy them cheap used on Craigslist.

black/white or grey is the key thing here...


And yes a shag rug is gonna do wonders in a room acoustically but for a working film set not very practical to cart around and setup.

So when I've had to goto a person's home for narration record I tried to get a walk-in closet or a room with carpet and heavy drapes.

Along with this thread topic I have recorded voiceovers in people's walk in closets.


I have also lined a small closets' two door doors with blankets held by spring clamps at the top and had the narrator face into the office's closet and record some VO. with the door open maybe 25 degrees. 


I have built temporary voiceover "booth" out of 5 blankets.

In a large very reverberant space I used 3 as a triangle hanging from C-stands, one laid over the top, and even one on the floor and gaff taped it down on the edges.

Boompole coming in from overhead on a stand.

I also setup a C-stand holding a small solid flag for talent to lay their script on and another lightstand with a 150w fresnel peeking in the top corner so they could see. We are talking about 2 minutes of VO to record immediately after host reads to camera on a set 50 feet away.



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I have 4x4 foam core with Auralux glued to them.  They were originally made to make a box around a ballast so it could get air and stay cool, as opposed to the old sound blanket on the ballast trick that made them hot.  These 4 bys became useful on a c stand to help with echo.  Sometimes just above the talent at an angle made all the difference.  They were just all around a good investment.

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Hey All,


Thank you so much for all your wonderful help.


I've been shooting in this place for 2 weeks now. We've been using about 30-40 furniture blankets.


2-3 on 10 c-stands which are placed around the action, and around 10-15 placed on the floor around the set.


Mostly using lav's for the mix, which with the blankets has actually eliminated a lot of the echo.

If there is a really loud sequence I've been using rycote overcovers which again helps to dull the echo.


I've also been getting quite a number of wild lines.


I feel quite confident now going into the next 2 weeks.



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