Workin' on the Railroad


"Post-production" is that phase of filmmaking which takes place after all the actors and cameramen have gone home. Most of it consists of the addition of, as well as dialogue, sound effects which for various reasons could not be properly recorded at the time of the original filming. In particular, scenes which are shot outdoors are often a nightmare for the audio crew, because while it is fairly easy to keep extraneous objects out of the camera's view, it is almost impossible to keep unwanted sounds away from the microphone(s). Nearby street traffic, overhead jet planes, even insects reconnoitering the microphone, can spoil a take at any time, and it is nearly always the take which the director okayed because it was the first (after two dozen) that the actors managed to get through without blowing their lines.

Because our world is so noisy, a film director will often choose to shoot "outdoor" scenes indoors, on a soundstage, adding any necessary scene-setting background sounds during postproduction. But even then, the ambient sounds must be "right." If the sounds of crickets and distant crows help establish a scene in a cornfield circa 1842, there cannot be a jet plane roaring overhead. This may seem like a trivial detail that no one in a theater audience would notice, but if the background ambience in a scene is wrong, the illusion of reality is impaired, even though the viewer/listener may not be conscious of what's "wrong" with the sound.

This is why postproduction houses keep on hand a large library of ambient (continuous) and incidental (one-shot) sound effects, meticulously cataloged and detailed as to locale and mood. And because usable effects are so hard to come by, most users prefer to buy them from someone who has already done the sweating and cursing, than send out their own people to collect them. Mobile Fidelity Productions of Nevada is one of their sources.

The firm's name derives from the mobility of its recording equipment. While MFPN's effects library includes many "small" sounds, their specialty is on-location recording of things too big to bring into a recording studio.

Such as trains.

And not your ordinary, everyday, noisy, smelly, diesel-electric trains, either (although MFPN has taped many of those too), but old-fashioned, romantic, noisy, smelly, steam-powered trains.

Few of us remember the days when coal was king on the railroads, nor indeed when the train was the fastest way of getting from one place to another. But prior to the late 1940s, when the inefficient, polluting steam locomotives were being phased out in favor of the new diesels, the passenger train was a continuing reminder to homebound citizens that there was a whole world of adventure and discovery out there beyond the bend where the tracks disappeared from sight. Thus was born the idea of the romance of the railroad, and its symbol was the wail of a distant steam whistle, reverberating through the valley on a cold, clear winter night.

That distinctive, mournful wail came from the fact that, although a steam whistle is a tuned resonant device, its pitch varies widely according to the pressure of steam forced through it. This was under the manual control of the engineer, who learned to "play" the whistle as a bugler plays his instrument, suiting its intonation and phrasing to the situation. (By contrast, the modern compressed-air locomotive horn has only two states; on or off. It's practically digital!) The engineer would sound a long, rising, sustained and then falling wail when the train was moving at speed in open country, to warn vehicles approaching crossing gates ahead. A short, sharp blast or two when the train was stationary would signal its intent to start moving, while a series of ululating hoots might express nothing more than the engineer's exuberance of the moment. The steam whistle's range of expression was almost limitless, its sound unique from one locomotive to another, and—heard from a distance—that sound was shaped in countless ways by the surrounding terrain. This, apart from sheer nostalgia for the sounds from one's childhood, is why train buffs never tire of listening to recordings of steam locomotives. But then, those of you who are "into trains" know this already. The preceding was for the benefit of those audiophiles who may have wondered what in the name of heaven it is that train buffs see (or hear) in those earsplitting recordings of whistles and thundering wheels.

For the audiophile who isn't interested in trains, recordings of them are nonetheless one of the best means of demonstrating—particularly to tone-deaf friends—the capabilities of a super audio system. Their dynamic range spans that of human hearing, and their frequency range goes from the infrasonic to the ultrasonic. There are, in fact. very, very few audio systems which can reproduce the sound of a passing train at its original volume level without crapping out or frying drivers. (We're talking here of SPLs approaching 120dB. That's LOUD!) The accurate reproduction of train sounds is as challenging in its way as the accurate reproduction of a symphony orchestra. It's just that the requirements for success are different.

But one area where music recording and train recording are similar is in the connoisseur's conviction that the acoustical environment is an integral part of the total sound. In music recording, the environment is the concert hall, and its acoustics are considered as important a part of musical sound as the "raw" sound of the instruments themselves. In train recording, the acoustical environment is the unique patterns of echoes and reiterations of the "raw" whistle sound reflecting from the surrounding terrain. The more convoluted the terrain, the more varied and complex are these reverberations, which was why MFPN chose the Cumbres and Toltec railroad for this series of recordings.

This narrow-gauge road, which joins Chama, New Mexico, to Antonito, Colorado, snakes a circuitous route along 64 miles of track to travel a straightline distance of a mere 35 miles, crossing the NM/Colorado border 11 times along the way. The terrain it passes through is some of the most spectacularly scenic and mountainous of any in the US through which steam trains still travel, and the track runs through expansive plains as well as around craggy hillsides.

Built in 1880 as an extension of the Denver and Rio Grande Western railroad, to provide a supply line for the mining operations in Durango and Silverton, it was also the route of a luxury passenger train (the San Juan Express) until 1951. The line continued to haul freight until 1968, when stiffening competition from highway truck lines forced it to cease operations. In 1970, it was purchased jointly by Colorado and New Mexico (as part of their Historic Preservation programs), refurbished, and reopened the next year for the edification and delight of train and scenery buffs. It has operated in that capacity during the summer tourist season ever since. (A trip from one end of the line to the other takes about 6 hours, and costs $41.50 per person. Passengers grab lunch and then change trains for Antonito at Osier, midpoint along the route. The Chama train then returns, and passengers are returned to Chama by bus.)

Footnote 1: Although both firms have the same name and use the same trademark, they are no longer associated.