Field Report: Diesel Train Sound Effects with Microphone Comparison

Courtesy of Buddahbless

Train Sound Effects

Train sound effects are one of my favorite field recordings to capture. Whether they are subway sounds, monorail sound clips, trams or streetcars, high-speed trains or electric train sound effects, I find that trains or “rolling stock” offer endless different sounds to record.

Similar to construction vehicles (like the drilling rig sound effects I posted), trains are mechanically specialized and incredibly complex. This means that they have potential for unique and interesting sound effects.

Some things I like to think about when field recording trains are:

power source – electric, steam or diesel
rail type – age of track, location of track (turned, straight, bridge, tunnel, etc.)
cargo – passenger cars, freight or solo engine
motion – speed, static position or direction

From my travels around the globe, I’ve noticed that recording trains are a great way to evoke a country’s character.

Spain, for example, uses four types of rail gauge different from the rest of Europe. In most cases this means passengers traveling from France to Spain must disembark and reboard, meaning different trains and distinct sounds.

Futuristic high-speed trains, sleeper trains and commuter trains all have individual voices. Recording these sound effects well will bring out characteristics of the type of train itself and evoke the country and spirit of where the train was recorded.

I’d love to record the bullet trains in Japan, but for now I may have to be satisfied with recording North America’s only high-speed line: Amtrak’s Acela Express trains. Both are on my field recording wish list.

Background

I was visiting a small town in Ontario a few weeks ago. I happened to be passing by the local train station with my recording gear on my shoulder. A diesel train was idling on the tracks for an unusually long time. Typically the trains stop only briefly in smaller towns before rushing away to larger cities. The train was obviously delayed.

In Canada, our federal government manages our train lines. This “Crown Corporation,” Via Rail, primarily uses General Electric diesel engines. The train idling on the track was a GE Genesis P42DC diesel engine pulling 5 or 6 passenger cars.

This train has 4,250 horsepower and a top speed of 110 mph (177 kph). Besides being used in Canada’s Québec City-Windsor rail corridor, it’s also used for Amtrak’s long-haul and high-speed service.

I approached and noticed that the environment was surprisingly good. I couldn’t hear birds, cicadas or traffic. This had potential to be a very clean recording.

The shoot

The train could depart at any time. I knew I had only seconds to start recording.

It’s easy in these situations to become excited at a golden opportunity. It’s important to remain calm. Becoming panicked, or rushing things can mean you’ll overlook a critical aspect of setting up gear or a problem with the environment that has to be accommodated.

I calmly set up the gear and punched in with two recorders. Rushing things would only make recording worse. A quick but botched set up wouldn’t be worth the poor sound effects I would capture by not taking time.

Other challenges:

accurately predicting the increase in engine noise when the train departs and setting levels appropriately
staying a safe distance from the track
not being disturbed by security
setting up equipment with limited time
isolating the microphones to minimize extraneous sounds such as traffic, birds, insects and curious people

Results

I ended up having more time than I thought. I managed to capture long section of the idle with various air releases before the train departed. The sound clips below are a portion of what I recorded and the most eventful part. A bell rings as the train departs slowly to the right. This is followed by the passenger cars scraping and squealing lightly on the metal rails.

The the samples were edited in sync. The first sample is from the H4n recorder. The next is the Neumann 191 microphone, powered by Sound Devices’ MixPre and the 722 recorder.

I placed the microphones at the same location. The H4n is recording at a 120° pattern. The Neumann is recording at a 100° pattern.

For reference purposes I haven’t equalized, processed or no-noised the recordings.

H4n:

Neumann RSM 191-i:

I found it interesting to compare the microphones. It may be unfair to compare microphones with such a difference in quality and price. I did find it makes me appreciate the expensive Neumann microphone, and reminds me of the limitations of the cheaper, but more portable, H4n.

Here are some diferences I noticed:

the Neumann sounds wider, and has more depth despite the pattern being narrower. The H4n is flatter, like a wall of sound
the Neumann captures more high-end, and a breathy aspect of the engine
while the ringing bell seems buried within the idle of the H4n recording, it seems to jump out a bit more in the Neumann recording. Additionally, the bell is placed slightly to the right in the Neumann recording
the Neumann seems to bring out more of the metallic aspect of the rail scrapes, as well as tighter low-end thumps as the cars pass over seams in the rails
the Neumann recording generally sounds more powerful
the Neumann appears to have more “soundstage” or available stereo imaging

Find more diesel train sound effects at my website airbornesound.com. Here are some more quick links to train sound effects on airbornesound.com:

general train sound effects
steam train sound effects
monorail train sound effects
streetcar, trolley or tram sound clips
some electric train sounds, recorded in South Africa
subway, Metro or underground train sound effects, recorded in various places around the world

Some thoughts

One of the tricky things about recording trains is the significant difference in level between the engine passing and the cars passing.

The engine with its heavy and oppressive motor will carry most of the power as well as the sensation of movement. It is incredibly loud, especially when passing at high speed.

The passing cars make little noise themselves, which makes them very valuable for capturing rail screeching sound effects.

Normally the rail sounds are buried beneath the power of the engine. However, freight trains can have endless lines of cars. After the engine has passed into the distance, you’ll have the opportunity to capture isolated metal screeches, grinds and groans without the diesel engine interfering.

Since the dynamic between these two sounds is significant, you’ll have to make a choice:

ride the gain after the engine has passed to capture the quieter cars at an optimum level
establish a fixed gain for either the engine or cars
record with two microphones, one set with the level attenuated for the engine, the other for the rails

Let me know in the comments below which technique you prefer.