Thursday, November 19, 2009

John Garrett on Sound

Rule Broadcast Systems has been hosting a series of lectures/workshops relating to video production. The Nov 11 workshop on sound featured sound mixer G. John Garrett.

John started with an introduction to the human auditory physiology; the parts of the brain that receive and process sound, and noted that the bone surrounding the inner ear is the hardest bone in the body.

He then asked, somewhat rhetorically; how do you know when the sound is right? Some one yelled out from the back; “when the producer says there’s no money left.

Getting down to specifics, John didn’t have many positive comments about on-camera audio hardware, noting about one camera “What do you think they spent on the audio hardware? Probably $50?” One audience member said she’s heard that the audio on the RED camera wasn’t that good, and he agreed, noting that the very first version didn’t even have audio, and that Sound Devices had tested the RED and found it to be closer to 12-bit sound than the claimed 16-bit [see link below, I can’t actually understand the article, so I don’t know whether they do say it’s closer to 12-bit or not.] Either way, John advocates dual system recording.

the Red One’s near 16-bit audio performance is similar to many of the digital pro-sumer and pro cameras we have tested. This is perfectly acceptable for dialog, especially when hit with a good, clean line-level signal. Sound Devices recommends dual-system sound for critical applications. – Sound Designs

One of the most important aspects of recording is the acoustical space, and the goal of the film maker is to reproduce an acoustical space that "matches" the visual space. In recording, this often means that you have to adjust the space to produce an “idealized” recording. Most importantly, while you can add reverb later, it’s almost impossible to take out afterwards. With that in mind, parallel walls set up standing waves and have a resonant frequency; you must reduce parallel walls to reduce standing waves

Temporary relief:
  • Carpeting
  • Furniture
  • Draperies
  • Sonex

While the goal is to reproduce sound accurately, as a counter example, he did note that in the helicopter scene from Apocalypse Now, somehow it’s incredibly noisy outside the helicopter, but inside you can hear them talking just fine! Sometimes the sound works, even though it’s obviously wrong.

John also told a story of visiting a local movie theater were they had the channel assignment wrong; the center channel was coming out of the left channel. He immediately went to alert the staff, who dismissed him by saying that the projectionist said it was okay. He was more than annoyed by this when he came back five months later and found the problem still existed. As he said, “I'm not just a cranky old man- I'm a cranky old man with portfolio!

He offered a number of tips, some obvious; Don’t go above 0!, Line level is preferred over mic level in case of any noise, and some not so obvious: It’s very hard to get “realistic” recordings of guns with digital equipment. Analog recording equipment does a better job of recording explosions and guns because the limiter works like your ear.

He concluded by listing some essentials for recording:
  • Mixer
  • Directional microphone hyper-cardoid or shotgun
  • Boom pole
  • Shock mount
  • Wind protection
  • Head phones
  • Lavalier mic
  • Bag to put it in and all connectors

Though this was just a fraction of the equipment he actually had with him both on a cart, and in a large travel case which he thought probably had “over 300” items in it. Doing good sound, it turns out, is a full time job.


* Sound is easy, you only need to know two things: what mic and where to put it!
* Where's does the boom mic go? Right on the edge of the frame.
* British DPs aren’t afraid of the dark
* I'm an old guy who believes in the church of the copper wrote
* Sound can be accurate or good
* Quoting another sound expert: Somedays you can be wonderful and somedays you have to be practical


What do you mean “dynamic range”? I'm playing as loud as I can -Musician

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