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Old December 15th, 2008, 06:42 PM   #1
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Extreme Echo in Small Room Help!!

I am Shooting in a room with hard wooden floors, no furniture, and mirrors on one wall. I am using a wireless lav for single person speech. The echo is cut down but not perfect.

Sometimes 4 people are "on stage" at once and the echo is too much. I am going to hang up sound reduction blankets on the wall to damper the echo, but this is not enough.

Someone told me to set up two mics facing away from each other to form an "X", reverse the wires in one XLR cable and that will create a cancellation of background noise. Is this right, or a bunch of bul*sht??
Would I have to connect to a mixer, then send the audio out to the camera as opposed to going directly from the mics to the camera?
Should I use shotguns, or handheld?

Is there a better way to reduce echo before post?
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Old December 15th, 2008, 07:31 PM   #2
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Hi Frank.............

The only way to kill that echo is to acoustically kill the room.

Soft covering on the floors (carpet or underlay) and ditto on the walls using anything that comes to hand - curtains, blankets, mattresses, you name it.

There is no electronic or software way to kill echo in such an environment, it has to be done mechanically.


CS
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Old December 15th, 2008, 09:08 PM   #3
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Frank Reco;978776]I am Shooting in a room with hard wooden floors, no furniture, and mirrors on one wall. I am using a wireless lav for single person speech. The echo is cut down but not perfect.

>>Why lock yourself in to a location from Hell? Can you shoot somewhere else more favorable?

Sometimes 4 people are "on stage" at once and the echo is too much. I am going to hang up sound reduction blankets on the wall to damper the echo, but this is not enough.

>>Four people and one wireless lav? That would cause the problem you are hearing.

Someone told me to set up two mics facing away from each other to form an "X", reverse the wires in one XLR cable and that will create a cancellation of background noise. Is this right, or a bunch of bul*sht??

>>Two mics with reversed polarity can reduce frequency noise, but that's not the problem.

Would I have to connect to a mixer, then send the audio out to the camera as opposed to going directly from the mics to the camera?

>>A good mixer is always a good idea, but would not help here.

Should I use shotguns, or handheld?

>>Definitely NOT shotguns. Youare not giving us enough information as to what you are trying to shoot. One person talking, four people talking? How many mics do you have?

Is there a better way to reduce echo before post?[/QUOTE]

>>Probably.

Regards,

Ty Ford
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Old December 16th, 2008, 12:32 AM   #4
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Sorry if I wasnt clear. I used to use my on camera mic, but that doesnt cut it. I bought a wireless lav to mic 1 person for a monolog or soliloque(forgive my spelling..). This reduced the echo from the 1 person that is speaking a good deal.

Other times up to 4 people do a scene at once. This is where my problem is. I do not use the lav in this case. I switch to the on cam mic, but i need a better solution than this.

I will be able to get just about as many mics as I need. Getting the equipment is not so much a problem, as is what to use and how to use it to reduce echo.

Change of location is not an option bc the person who is running it requests this room. I have no influence over this decision.

I will def pad up the room. Thanks for the advice so far...
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Old December 16th, 2008, 01:11 AM   #5
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Oh, well that's better.

If you are working with scripted dialog, then you need a good sound person with a boom pole. If you can't get that, then you need to mic everyone seperately with lavs and send it to a decent 4-track recorder and run dual-sounnd. Sync up in post. Just like you were shooting real film. This will reduce the echo, and give you nice sound all around. Honestly, with as live as that room is, I'd be using the lavs hidden under the first layer of clothes. Try to slow down some of those reflections.

Not a fun problem to have.
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Old December 16th, 2008, 04:52 AM   #6
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Quote:
Is there a better way to reduce echo before post?
Other than Chris's post early in the thread, this part of the question fell through the cracks. ALL echo reduction must be done before post. There is no filter or post-production technique that can remove reverb from the track once it's in there. You have to fix it at the source. Once it's recorded, you're stuck with it,
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Old December 17th, 2008, 09:11 PM   #7
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Conventional wisdom is that hanging blankets need to cover two perpendicular walls to be effective. In practice, this is rarely possible, at least for me, due to lighting, time involved, or whatever. It's definitely worth it though, if you can manage it. As mentioned, the on-camera mic is the worst possible choice for this situation.
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Old December 17th, 2008, 10:19 PM   #8
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I have sound resistant blankets. Today was one of the days that I was in the room, but I was unable to hang them bc of a lack of time. Im not sure how to hang them either. I cannot pin, staple, nail, tack or any other thing that would go into the walls. The blankets are too heavy to tape...It seems like the only option left is to support them with a c-stand or something similar. I dont have anything to suspend them like this.

This really isnt a huge production and I am starting to move out of my budget, so I will just lay some blankets around and thats the best I can do.

I really appreciate the advice from all of you. Thanks to all.
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Old December 18th, 2008, 04:41 AM   #9
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Use light stands to support the blankets out of camera range.
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Old December 18th, 2008, 07:33 AM   #10
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Dean, what do you use for the cross beam when you do that?
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Old December 18th, 2008, 11:33 AM   #11
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Marco...

I just use a 1/2" diameter aluminum tube. The sound blanket is fastened with spring clips. Fast, easy and cheap.
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Old December 18th, 2008, 02:29 PM   #12
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Interesting. How do you attach the crossbeam to the stands?
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Old December 18th, 2008, 11:43 PM   #13
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Mafer Clamps. (aka Super Clamps)

(Tho there are probably 100 other ways to do this as well.)
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Old December 19th, 2008, 05:28 PM   #14
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new trick, siamese a pair of 40" arms ( one grabs the other facing opposite direction ) in a C stand. makes for a nice wide reach, grip clip as usual. even just a single 40" arm will do, better then nothing, problably sitting there on the set to start with. you could also use a 4 / 6 / 8 ft side from a frame, mount that on a C and hang 2 blankets.

going with the DYI approach, I'd get a 1" - 1"1/2 peice of Aluminum pipe or square tube, drill 5/8 holes in the ends so they line up vertically, and you can just drop it onto the top of a stand. I'd drill the middle too. no clamps required.
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Old December 22nd, 2008, 04:45 AM   #15
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i'm a big gear whore, but... if its a choice between not hanging the blankets due to cost of proper gear vs. using ghetto gear, i'm all about the ghetto. screw brooms together. tie tree branches together with rope... anything you can use to get padding on the wall will help. Yeah, c-stands with a truss would be ideal... but i guarantee if you get creative you can get some fabric on the walls for less than the cost of a trip to starbucks. Might be ugly, but sound isnt about looking pretty. Photos of professional audio guys will reinforce that point. OY! :,>
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