sound design--Voices through a wall

[humptydude04]

Hey everyone,

I'm trying to plan out my sound design ahead of time to save myself some headaches later and I know I might have trouble with a scene where a character is listening to a fight through a wall (a la Little Miss Sunshine). Can anyone give tips on how to achieve that sound? Do you literally record the dialogue through the wall or record it directly and filter the hell out of it? Thanks in advance!

 

[Red Prince]

I would filter it, removing the high frequencies.

 

[professor aire]

If you don't have the option of recording the dialogue through the wall on-set (which can be frustrating having to coordinate on-set) then record the argument separately and, rather than filtering it, find a quiet location with two rooms and a good wall that lets a fair amount of sound through it and set a good pair of speakers up in one of the rooms. Set your recording equipment up in the other room and play-back the argument through the speakers recording it a second time as you do so. This'll get you a more natural sound and has the added benefit of letting you adjust the volume of the argument to achieve the sound you need without asking your actors to destroy their voices.

 

[humptydude04]

That's a great idea. Thanks for the input!

 

[Red Prince]

I would still filter it. That gives you greater control over the final product.

 

[humptydude04]

Any suggestions as to how to filter it? I'm not that great with audio software.

 

[Red Prince]

Cut off the high frequencies (low-pass filter). You need to experiment with it to find the right cut-off frequency, i.e., the frequency above which the filter will start cutting. Start at about 2000 Hz and go from there, either raising that frequency if you need a less strong effect, or lowering it if you need a stronger one. Also play with how much to cut off (i.e., 10 dB, or more or less than that).

The reason why it is better to use filtering than actually recording through a wall is that you want to make sure that, while the sound is muffled, the voices still can be understood by the audience.

The book Producing Great Sound for Digital Video, by Jay Rose, explains these principles. It also explains the filters in its Chapter 16. Though you may want to read the first four chapters first. Get it from the library if you can't afford it.

 

[humptydude04]

Fantastic. I appreciate all the help. I couldn't have done it without you guys! Thanks again.

 

[professor aire]

Red Prince is correct in that filtering the dialogue can give you greater control over the sound... The reason I brought up (and would always work with first if given the time) recording the dialogue through the wall is that it can give you a more natural response and even timbering. There are often natural reverb and frequency abnormalities brought about by the wall itself, the hallway between the rooms, the doors to the rooms, etc. For example: a wall that has been insulated compared to a wall that hasn't been... the two will sound vastly different and each have their own perks. A bearing wall may very well sound different than a standard wall.
Making sure the dialogue is understandable to the audience is where the equipment used to re-record the dialogue is critical. If you use a crappy pair of computer speakers to playback the audio, you'll get crappy results. If you use a $50 dynamic vocal microphone to re-record the audio, you'll get substandard sound. If you don't have a good recording set-up, filter away... If you do have a good setup; I'd at least give it a shot. It'll at least be a learning experience.

 

[Bob Kessler]

To summarize from previous posts, worldizing the sound by playing the scene through a quality speaker set-up and re-recording with a quality recording set-up will give you the most natural sound. This is a common practice amongst sound designers.

The beauty of modern DAWs is the flexability available at mix time. Do the worldizing (provided you can do it properly) and then layer the results with the clean recording. This gives you the most natural sound and the ability to improve intelligability as needed.

If you cannot wordlize using a parametric EQ to simulate the effect requires some patience. Using just a low pass filter is the easiest way, but not the most accurate. You should also reduce some of the lows and upper-mids selectively as well. You will also have to add a little reverb.

Impulse Response reverb softwares such as Altiverb have pre-sets for "through-the-wall" and many other situations that can be tailored to taste. This is the easiest way (if you have an IR reverb program) as it is an actual computer model of how sounds respond in real world situations.

Good luck!