When your movie is all about a runaway train, you need sound effects that convey the mass, momentum and danger of that disaster in waiting. For Mark Stoeckinger, sound effects editor on Unstoppable, the challenge was to work with director Tony Scott to convey something of the experience of being next to the tracks when a huge locomotive barrels by at high speed, as well as to help give the train in question, known as the “Triple 7,” its own villainous presence in the film. Film & Video asked Stoeckinger, an Oscar nominee for his work on the film, to talk about making a menacing soundscape.

Film & Video: How early did you get on board the Unstoppable train?

Mark Stoeckinger: In the midst of the director’s cut, I came in and started conceptualizing and developing the sound.

Is that typical?

They’re all a little different. The commitment for me to work on this film just didn’t happen until that time. On Star Trek, as an example, we had our first meeting before they shot anything. We talked about tech settings and nomenclature, but I didn’t stay on the film at that point. I just started the process and then came back right around the end of shooting. On Unstoppable, I started later in the process. On some films, it’s later yet. I might not come on until a couple of weeks before the first audience preview. The process is forever evolving. Some people need somebody who’s going to create their sound early on. Films that don’t have as much subjective sound can wait until later in the process. Every film has different needs, but the earlier you’re on a film the more helpful it is.

So what was the first order of business when you got started on Unstoppable?

I sat down and ran the movie with Tony [Scott] right off the bat, where it was sitting. He explained his intent and what it was about. That’s a good way of getting into the filmmaker’s head so we can get started with our work.

I have to imagine that it played as a very different film before you started doing that work.

Sound is important enough to him that he does a considerable amount of sound work as the picture is being cut, using a number of different sources. He actually tasked us with making a great sound library he could use, or taking things that were recorded on set and mastering them in a certain way, or getting more of those things. He’s a very sequential filmmaker. He doesn’t want to put a lot of extra things in until he understands what his cut is going to be.

What were your marching orders? How did you get your arms around the project?

The first thing was to understand what they had done on the set. Tony always wants to start off with a strong production track. If there’s a train going by, he’ll start with the production sound. At that point, he lets you elaborate on it, either by putting other pieces in there that came from the production, things that you record, or even things sourced from a library. And he always wants to know what the source was. He was very specific on how he experienced trains while shooting the movie, and it was important for him to capture that on the soundtrack. If he was right next to the tracks with a camera and a train went hauling ass by, shaking the ground, and he got the feeling of the clickety-clack of the rails and the weight of the rolling wheels, he wanted to extend that to the audience.

We recorded a lot of sound. It’s the same as a documentary filmmaker – you go out and you know what you want, but you make sure you capture all you can, and you determine what’s best suited for the soundtrack and the story you’re looking to tell. Tony would identify something and say, “I like it when the train does this.” We’d say, good, we need more of that and we need to be able to control that sound. And recording more of that is a story in itself. For example, the sound of the Triple-7 train that he liked was the sound of dynamic braking. The train happened to be making that sound, which Bill Kaplan recorded on set, and Tony liked that as far as the bad-guy train goes. But we had only a couple of seconds of that sound. We went out and Ken Johnson, who did a lot of SFX recording on the movie, had to pace trains. You find tracks that run close to the road, drive alongside them at the same pace, and find mics and mic positions where you can record that and get not just a lot of wind noise, but really capitalize on that one sound the train was making. The Triple-7 almost felt like a dive bomber – there’s something about the whine of that sound so that when it’s coming in forever before it hits the horse trailer, for example, it’s got that really intense feeling. Alan Rankin, one of the sound-effects creators on the movie, took those recordings, made a lot more of them, and made them do what we wanted wherever we needed anywhere in the movie. And that’s just the sound of that train.

Tony also talked about the heavy wheels. It wasn’t so much the rolling of heavy wheels as it was the clickety-clack classic train sound. But that sound isn’t prevalent anymore. They weld all the rails now, and trains don’t make that sound unless they go across a switch or a crossing. We went on many recording excursions where we would go to a crossing or rent time on various cars attached to trains, from L.A. to San Francisco, going across a lot of those crossings to get that sound. For the clickety-clack sound, Ken Johnson took a private car from Arizona through New Mexico on a not-very-often-used bolted-rail track that gave him the clickety-clack sound. They recorded a lot of on-board sound for that, which ended up in the grain-storm sequence. It was a dangerous-sounding sound. That’s how we mined a lot of sounds that were specific to the film, based on Tony’s direction.

How do you convey the mass and momentum of a runaway train?

You want that big feeling of weight, but not a rush of low end like it is in real life. You want it to have all the typical train sounds to go with it, like the sound of the engine, but also the rails and wheel and clickety-clack and all that sonic energy. With those various elements, Tony paints an audio picture, much as you might paint a visual picture, on a mixing stage, taking the pieces we would provide and sculpting the mix that he wants, or asking for other sounds that would help him sculpt in a different direction. It was all related to his desire to give it a lot of energy, all related to that train – the story where these sounds were occurring.

Do you collaborate a lot with the film editors?

A lot. There was a lot of sound work done in the Avid while they were cutting the movie, and we had to contribute to that. Tony works with someone who does a fair amount of commercials and trailer work, and he has him doing certain sequences of the film, some of it pictorially and some of it sound-wise, and some of those sounds propagate throughout the movie. He’s very good at working with different people to get a complete package. The picture editors had a lot to do with it, so we collaborated a lot with them – making sounds, giving them sounds, and finding sounds to make certain elements even more exciting.

Did you go through a lot of versions of the film for preview screenings?

The film was always fairly tight from the very beginning. Certain aspects of the story just got honed a bit, but most of that work was to maximize the excitement. We had two preview screenings and they went very well. The studio was positive on the film, and the preview screenings helped that immeasurably.