Exploding Bridges and Bowling Pins

In Sam Wasson’s fantastic new book about Francis Coppola and American Zoetrope, he quotes Walter Murch ruminating on the sound of colliding bowling pins. I remember those pins well.
When the helicopters attack the village in “Apocalypse Now,” a wooden bridge gets blown up by American rockets. As one of Walter’s assistants, my main job for many months was finding sounds to use in the film. We didn’t have access to any of the big movie studio libraries, and there were pretty close to zero commercial sound libraries in those days, certainly none that had Vietnam War related sounds, so we had to go out and record a high percentage of the sound effects we needed for the film.

We could have found a large wooden structure to blow up

Walter showed me the sequence where the bridge is attacked, a section of it shattered. It looked like several tons of timbers and planks splintered and flying through the air, banging into each other. We had recorded lots of explosions for the movie… grenades, bombs, gasoline, etc., but nothing where big pieces of wood get exploded. We could have found a large wooden structure to blow up, but that would have been expensive, and there was no guarantee that we’d get the wood aspect that we wanted. Very little useful sound was recorded on set while they were shooting the movie. It was way too chaotic, so we had to invent nearly all of the sound in post production. To make the sound of that moment feel authentic, I needed to find woody elements to add to the basic explosion sounds we had already made in post.
I tried lots of things: trees being chopped down and falling, hitting wooden telephone poles with sledge hammers, throwing pieces of lumber around, etc. I think any of those sounds could have been useful layers, and a couple of them were helpful, but they didn’t quite sell the moment. I wracked my brain to come up with situations in which lots of pieces of wood collide with each other. The idea of bowling pins bubbled to the surface.
I suspected it could be a waste of time. Bowling pins are small compared to the size of the structural parts of the bridge in the movie. Bowling pins don’t typically shatter like that bridge wood did. And the sound of bowling pins is so identifiable and familiar… wouldn’t people in the audience recognize that sound immediately, and wonder why they were hearing a bowling alley in a battle scene?
What the heck, I spent about an hour recording in a San Francisco bowling alley. They let me put microphones in various places, including at the back of the alley, behind the pins. When I got the recordings to the studio, they definitely sounded woody, and it was cool that there were a bunch of hits in close time proximity, so I wouldn’t have to build a mass of them individual hit by individual hit. But to my ears they were so obviously bowling pins, and the sound of them felt too small to be elements of so large a bridge.

We didn’t have digital sound processing in those days, but we could make a recording on tape sound bigger by slowing down the tape playback speed, then transferring it at the slower speed. I played the bowling pin recordings at half speed and one quarter speed. Now the pins sounded like they were about ten feet tall. What wound up in the movie was a mix of regular speed, half, and quarter speed pins colliding. As to whether it’s too recognizable as bowling pins… the idea seems never to have occurred to anybody but me. I still hear that bowling alley when I watch the scene, as I did yesterday. To everybody else, it feels like we had microphones all over that bridge. Such is the power of sound design.

The Connoisseur of Mistakes

Great art depends on accidents and mistakes.

Most non artists think that a work of art begins with an imaginary, grand design, which is then made real by using the techniques the artist has developed. That’s not the way it usually happens. It’s certainly not the way interesting art usually happens.

In the beginning there is most often nothing, and more nothing, and nothing for hours, days, and sometimes weeks and months. There are scores or hundreds of false starts. Then, when something does pop into the artist’s head it isn’t anything close to a grand design. It’s usually an inkling, a notion, a fleeting feeling. It’s an unintentional smear in one corner of the same canvas the painter or sound designer has been fruitlessly fiddling with all along. But it suggests something. It’s a start, only an idea, a hunch, but nevertheless something concrete to work with.

You don't "invent" a sonic world...

People think that doing sound for animated films or for live action sequences that are mostly computer graphics must be especially challenging because it involves “inventing” a sonic world. Not really. For one thing it isn’t accurate to say we “invent” anything. We discover, and the distinction between inventing and discovering is very important. To “invent” or “create” implies something comes from nothing. In fact, what we do is to borrow, and then when we’re lucky we find a way to use the borrowed goods in a new, original way. For example, there is no doubt that Picasso appropriated images in African art for some of his most famous paintings. (http://www.pablopicasso.org/africanperiod.jsp)
So, if “creating” is really about discovering something that is already there in a different or scattered form, then how best to do this discovering? You have to become a connoisseur of mistakes, accidents, and the unintentional. Very few people in human history have been so lucky and/or so brilliant that they actually invented anything. Even Einstein, coincidentally peaking about the same time as Picasso, borrowed from the work of many others as he developed his theories, but it was an “accidental” image of someone falling through air and not being able to feel his own weight that was probably the key to developing his theory of general relativity.

At the start of a project I learn as much as I can about what the director and writer have in mind in terms of the story, the characters, and places (they usually haven’t thought much at all about sound), and then I start randomly listening. I listen to sounds in the library and on the street, randomly. As I do it I’m not thinking “I need the sound of thunder,” I’m just skipping around from category to category listening to whatever pops up. Most of it won’t suggest any connection to the project I’m working on, but it usually only takes a few minutes of random listening until I stumble upon a sound that feels deeply connected to the project, and often it’s connected in a way I would never have anticipated if I had just started making a list of what kinds of sounds I thought the project needed. When I’m going about my daily life during the project, I try to be open to the same kinds of obliquely but profoundly related sounds. Sometimes it isn’t the spectral content of the sound at all, but a certain rhythm or a certain change in dynamics.
In “The Right Stuff,” when Yeager’s rocket accelerates, the high pitched sound is a piece of chalk squeaking on a slate board. I had gone to an old school to record doors, but happened to hear a brief chalk squeak, and it occurred to me that several of those cut together could express the scary intensity of that rocket, like it was on the edge of exploding, screaming through the air.
I try to train my ear to get better at these things, to begin with as few assumptions as possible, and to be open to the unanticipated sounds rolling past me that glue the story together better than any grand design I could have dreamed up.

On a Roll

by Randy Thom
It’s a little-known fact that the sound of a rolling object is caused by impacts with the surface it is rolling on.
The more frequent the impacts, the smoother the sound. This is even the case with a hard sphere rolling on a rigid, flat surface. Though if it’s a near perfect sphere and the surface is near perfectly flat and hard, the sound generated will be minimal, because the impacts are minimal.
How is knowledge of this phenomenon useful to sound artists?
Let’s say you’re trying to produce the sound of a walnut rolling on the ground. Literally recording that action can render something useful, but realizing that what is really making the sound is impacts, AND DOESN’T REQUIRE THE WALNUT TO BE ROLLING AT ALL, opens the door to creating a more tailored, stylized sound that can be far more expressive and “musical” than what you are likely to obtain by literally rolling the walnut across a surface.

How Do You Simulate a "Roll"

To simulate the rolling sound while giving yourself a lot more control: don’t roll the walnut. Simply tap it on a given surface several times. This simulates what is physically happening during a roll. The taps should usually vary in intensity, the intervals between the taps should vary, and the distance from the microphone should vary, so that the result will sound naturalistic.
To give it more character and make it more “musical,” tap the nut on a series of different surfaces to simulate a more complex-sounding journey. You would have to do lots and lots of takes to get a similarly diverse and interesting a sound by merely rolling the nut.
By the way, varying how tightly you hold the walnut as you tap it will render a wider variety of sounds. Holding it more loosely will allow it to resonate, like a loosely held wine glass will ring way longer than one that’s held tightly.
For the Super Mario movie, I edited a sequence of exaggerated punch sounds to create the sound of Donkey Kong rolling himself rapidly along an i-beam. I’m using a similar approach for a fun sequence in the upcoming “Ultraman: Rising” movie.
This same approach applies to using library sounds to simulate a rolling object. The sound of a giant boulder rolling can be created by editing a series of explosion attacks closely spaced. The editing can either be done manually on a timeline (which is the way I usually work) or by using a sampler. Be sure to quickly fade down the decay of each explo so that it doesn’t mask the attack of the next explo. The SOUND IDEAS libraries are filled with great material for building this kind of sound design. Happy Rolling!

Why Microphone Placement Trumps Microphone Type

Placement vs Type

In the world of audio recording, the debate over microphone type and brand has raged a hundred years, largely fueled by individual mic manufacturers’ and retailers’ desire to increase their own market share.

​Audiophiles and professionals invest considerable time and resources in acquiring the latest and greatest microphones, believing that the ones at the high end of the price spectrum will significantly elevate the quality of their recordings. While type and brand are clearly something to consider, it’s arguable that microphone placement, the often-overlooked element of the recording process, holds far more sway over the ultimate quality of a recording.

Microphone Placement vs Microphone Type

Unlike fifty years ago, there are now huge numbers of high quality microphones of every type.

The differences in frequency response, noise, distortion, and dynamic range are relatively minimal within a given category of mics. While I wouldn’t discourage you from using the highest quality mic you can get, I know of thousands of recordings made with mid to low quality mics that sound really cool, and nobody would know what kind of microphone was used just by listening.
More of the magic happens with mic placement, in my opinion. The way a microphone is positioned relative to the sound source will always dramatically affect the resulting recording. Here are some reasons why microphone placement often takes precedence over type and brand:

    1. Every sound source emits audio in a unique pattern and is shaped heavily by the surfaces around it. Placing a microphone in a strategic spot allows you to capture what is unique and desirable about that place in time. 

    2. Likewise, microphone placement can help reduce what may be not so desirable: background noise and unwanted reflections.

    3. Adjusting the microphone's distance and angle will influence the dynamics and frequency range of the recording. Closer placement emphasizes proximity effect, while angling the microphone will alter the tonal characteristics.

    4. Room Acoustics: The acoustic properties of the recording environment play a significant role in audio quality. Proper microphone placement can mitigate the impact of poor room acoustics and enhance the overall recording. And more distant mic’ing can allow you to capture what is beautiful about an acoustic space.

    5. Artistic Expression: Microphone placement is an art in itself. Producers, engineers, and sound effects recordists often experiment with different positions to achieve a unique sound that complements the artistic vision of the recording.

    6. Budget-Friendly Solutions: Skillful microphone placement can compensate for the limitations of budget-friendly microphones, making it possible to achieve professional-quality recordings without breaking the bank.
My point is not that brand and model don’t matter at all. Though I do think they matter a lot less than we tend to think they do. What I’m suggesting is that spending time experimenting with mic placement is likely to make a bigger difference in the recording than the difference between two different mics. It’s also one of the key ways a recordist can create a style.
You can listen to this comparison of a Neuman U-87 and an AKG C414 here on Youtube. They sound almost identical. You can easily make up for these kinds of differences with eq. Move either of the mics back only one foot, or one foot to the side, and the difference in sound will be very significant. 

Artistic versus Technical Creativity

Differences between Artistic Creativity and Technical Creativity

I recently posted a piece on social media in which I talked about how little respect is given to sound teams on movie and video shooting sets. In the piece I said that very few production sound mixers have truly creative relationships with their directors, and that the job of recording the actors speaking on sets, in most cases, is far more an engineering job than a creative job. The purpose of the post (as a whole, it went on for several paragraphs) was to suggest that one of the reasons production sound people get so little respect is that the work they do is perceived as being mainly technical, not artistic.

Creative On-Set Microphone Placement

The post also said that films and sound people would benefit if directors and producers were to allow the production sound team to have more artistically creative roles.
I’m happy to report that the post got lots of praise, but it also made some people angry at me for suggesting that jobs like microphone boom operating are not very artistically creative. Some pointed out, correctly, that creative thinking is absolutely necessary when mic’ing actors.
So, what’s the difference between being creative at a technical job and being artistically creative? I think it’s something like this:
To be technically creative is to use your imagination to facilitate a process … to make that process more efficient, more accurate, less costly, etc.
To be artistically creative is to use your imagination to create an idea in the mind of the person who perceives the work.
Scenario 1: A boom operator devises a clever plan to hide a microphone behind an object on a movie set. This technique does not create an idea in the mind of the audience that they wouldn’t have received with a less clever mic placement. It DOES make the process of capturing what the actor(s) say more efficient and accurate than it would have been otherwise. And it does involve creative thinking.
Scenario 2: A boom operator makes this suggestion to Francis Coppola on the Saigon hotel set of Apocalypse Now: “Francis, if we get a shot of Captain Willard’s (Martin Sheen’s) pov of the ceiling fan above his bed, then in post production they can use the sound of helicopter blades for the fan.” This suggestion, if the director decides to implement it, will create the idea in the mind of the audience that the Captain Willard character is hallucinating and/or remembering the sounds of battle as he lies in his hotel room.
Of course it’s the job of the production sound team on a film/video set to record the actors. But in my opinion, it should also be their job to help the director figure out how best to use sound ideas in the story. One job involves technical creativity, the other involves artistic creativity.