The importance of sound in modern film is simply undeniable.
When we decided to tackle the subject of sound, I knew that to do it justice we had to approach it like building a foundation for a house: building it up brick by brick. For many filmmakers, sound is a mystery blended with bits and pieces of understanding gleamed through practice – that was the way I was before doing the research. That’s a clumsy way to go about learning. If we really want to understand sound and become masters of it, we have to start and the base and build up from there.
So I designed this series of audio lessons to move from broad base understanding to the specific application. Here is a map of the six different videos in our audio series and how they relate to one and other in progression:
Before we break down each video, I would like to take an opportunity to thank our sponsor RØDE Microphones who have been a tremendous support on this project.
1. The History of Sound at the Movies
I cannot exaggerate the importance of history. This is the longest of the lesson in the series and we cover from the beginning of sound on film (which despite conventional wisdom, The Jazz Singer was not the first film with sound or recorded dialogue) up to the sound technologies of the 1990s.
The first major point for filmmakers to think about in this lesson is the dramatic change that sound brought to the filmmaking process. As with all our history courses, I want you to put yourself in the shoes of the filmmakers at the end of the 1920s – watching an entire industry turned around and retooled in the matter of two years or so. Think about the implications for this art form – at the beginning of sound, debates raged over whether sound was suppose to be natural or augmented with things like sound effects and music. The dust did finally settle and what emerged was something that really didn’t resemble the silent film of only a decade past. When sound came about… silent film died and a new hybrid art form of motion and sound was born.
After the industry switch, sound technology stagnated for about 20 years. It was until television mortally threatened all of Hollywood that the industry started to experiment with multichannel surround sound. Even then it tool another 25 years or so before finally settling on the widely adopted Dolby Stereo format just in time for the film that would go and redefine the cinematic experience: Star Wars.
2. The Science and Engineering of Sound
This lesson takes a different angle on building the foundation – whereas the history lesson looked at the social implications of sound and film, here we look at the science of sound, beginning by defining five properties of sound: Amplitude, Frequency, Phase, Harmonic Content, and Envelope. We then define what a decibel is and the cover two common microphone types (dynamic and condensers) and the different types of pickup patterns from mics on the market.
The concepts about sound properties laid out here are crucial once we get into the sound editing side which will manipulate these properties. The engineering portion of this lesson is mean to give a basic underlying understanding to how microphones work. By understanding their internal function and the characteristics of microphones on the market we can better make choices for recording audio on set or on location.
3. The Basics of Recording Audio for Digital Video
With a foundation of history and science, we now move into the general application of sound recording. The best way to approach this subject was to look at the audio signal chain – that is how sound goes from air waves, into electric signal and finally being recorded onto a digital medium.
But in this lesson, I decided to work backwards – starting at the end of the chain and working toward the original audio waves. By looking at the equipment used for recording we also cover some of the key settings for audio recording including sampling rate and bit depth. Moving up the line I clarify the ingenious technique of audio signal doubling in balanced cables which leads us finally to beginning of the audio signal chain with mic placement and usage.
4. The Fundamentals of Sound in Post Production
Now that we have our sound recorded what do we do with it? In this lesson we cover the four types of filters commonly used in audio engineering including: Equalizer, Dynamic Range Controls (compressors), Noise Reduction, and Time Delay effects.
Now admittedly when I first started playing around with audio tools as a kid I had no idea what half of these things did (just that the reverb filter made it sound really reverby). But with a foundation in science of how sound works, these filters suddenly make more sense.
When you open up your audio editor, you will find a lot more advanced versions of these four basic types of tools (for instance Adobe Audition uses FFT for a lot of really powerful noise removal tricks) but if you understand how EQ affects frequency, how compressors reduce dynamic range and how Time Delay effects can color your sound, you’ll have a good grasp to begin working the sound in your film.
5. Introduction to Automated Dialogue Replacement (ADR)
Putting it all together for the first time, we explore a common practice in filmmaking: ADR or looping.
I used to be of the ilk that ADR was something that you wanted to avoid at all costs – I have only done it once before in a short film and honestly I didn’t find that experience all that unpleasant. I knew it was a tricky affair.
But when I started to research the history of sound and look at how ADR (called looping before computers got in the game) freed up camera movement in the early days of sound cinema, I realized that ADR was a much maligned technique. Ideally you want to capture the performance with natural location audio but ADR, if planned for, brings so much freedom.
Now my approach may have ruffled feathers of some ADR purists who think that ADR should only be attempted by professionals. With exception of panning the dialogue (which I learned too late that I shouldn’t have done), I stand by everything as it is explained in the lesson.
ADR is much like a magic trick, the first time you do it you may screw it up. In fact the first ADR session I ran with my actors didn’t cut together well. I brought them back in and we did a second take, this time reviewing each line as I placed them to see if we could make it better. It was a great learning experience for myself and my actors. As you get better the magic trick becomes more subtle – hopefully to the point where if the audience doesn’t know to look for it, they won’t even see it… or in the case of ADR… hear it.
6. Introduction to Foley and Sound Effects for Film
Once you replace dialogue with ADR, the next thing is to replace all the sound effects. In this lesson I wanted to dive into the world of Foley and look at the interesting history of the man that lended his name to this technique.
This was a challenging lesson for another reason all together. After filming the short demo film and the lesson I had a catastrophic hard drive failure that wiped away everything. So I had to reassemble my actors and reshoot the entire scene. Oh well, second time’s the charm. And now I have a pretty beefy back up solution in place.
Foley and Sound Effects really do bring a scene to life. As I was putting this lesson together I started really to pay attention to all the little noises that occur in my everyday life – the sound of my shoes on the carpet, the sounds of car doors (I always notice how nice car doors sound in the movies), the sound of a simple scratch. These little things simply don’t get picked up in the production stage and have to be added in post.
Although Foley can be a little challenging, ultimately it’s a lot of fun putting in those finishing audio touches and hearing your film come to life.
I really hope that this series on audio changes the way you approach sound in your films. In have learned a lot in researching this series but these were never intended to be the “the final word” on the subject -rather they are a chance to introduce topics so when you do more research or listen to interviews with audio professionals, you’ll have at least a context of these concepts and where they fit inside the audio world.
We have done our best to put together your foundation, but if you want to advance in sound, you’ve got to get out there and start practicing. Stay tuned – major changes are coming to the site which will give you a chance to practice with us… Keep your ears open and make something great.
John P. Hess