In filmmaking, it is often said that the eye forgives and the ear does not.
This means that even if your image isn't perfect – If the sound is off even a little bit, it will pull your audience out of the movie.
You don't want that!
Two frequent questions we receive revolve around how to record surround sound and how to edit in surround sound.
Here to help us answer these audio questions is Richard Ragon. He is a production sound mixer based in Los Angeles and he really knows his stuff.
How To Record Surround Sound
If you are looking on how to record surround sound – Specifically, the actors voices for a film, movie, or show of some sort, I have good news.
Surround sound, specifically 5.1 audio is NOT actually recorded in the field.
“Believe it or not, the human voice does not speak in 5.1, nor stereo either.”
The human voice is actually a mono instrument, and because of this, we are able to place a mono microphone near someone's voice to pick that recording up.
In fact, each voice recorded on set has it's own individual track.
There is a way to record multi-track audio, but it is used to record mostly SFX type work. One common example would be a train going by outside. For this you would just use 2-4 matched mics, in close proximity to each other.
It is important to note that 5.1 is a delivery system only. It is created in the post process.
Specifically this type of Surround Sound offers a way to create a spacial environment using 6 speakers in order to trick the listener into thinking they are in a 360 degree environment of immersion. In this scenario, 5.1 (or 6 speaker or tracks) has been set as the minimal speaker set, used in attempt to re-create a full sound environment.
With advances in sound technology, 5.1 has become somewhat of a standard playback. Additionally, we have seen an emergence in 7.1 audio, and now Dolby Atmos which I believe is near 128 individual tracks or playback.
The multi-track use is for creation of an environment. The .5 is not necessarily it's own track, but more of a way to separate out the lows to be played on a large low range speaker. This gives you the ‘booms' of explosions in a room, while the other 5 speakers carry the higher frequencies.
Higher frequencies are directional, so these other 5 speakers are placed around the listener to give the effect of 3d space.
The ‘voice' of actors, because they are on the screen right in front of the audience, is pushed to the front speaker(s) in post.
Planes flying overhead are made to sound like they go from one speaker to the next, like a real life fly by… And then music can come from all the speakers so your audience is emerged in the music.
Final Thoughts On How To Record Surround Sound
The bottom line is the sound designers on a film, organize all the tracks (voices, SFX, ambiance, et al…) In fact, depending on the movie, this can be as many as a hundred tracks! From there each recorded sound is pushed towards the front, side, back, or below, to a final output of six tracks (5.1).
Protools Software can be used to make 5.1 playback, as well as Logic and Garage Band. However, you will need some very large computers set up in a studio to do this kind of work in post.
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Richard Ragon is a production sound mixer (sometimes referred to as a location sound recordist) working in the Los Angeles area. For more information, check out his website.
