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How to Record Artillery Sounds

Next week we will be releasing an exceptionally rare sound collection of artillery sounds. We’re quite excited about it. Today’s post will take a first look at the sound effects to give a preview of what you can expect in next week’s release.

Want to learn how to record your own cannon or artillery sounds? You’re in luck. This article will explore how our team researched, planned, captured, edited, and curated the sound effects.

A Hunt for Artillery Sounds

Field recording is tricky for any handful of reasons. Invasive problem sounds, managing complicated equipment, and other issues can derail a sound effects gathering session. Some of the most challenging sounds to capture are subjects or environments that can’t be controlled – the recordist is helpless when things or places don’t act how they’d prefer.

So it was with great fortune that I heard the booming sound of artillery fire while walking home in downtown Toronto, more than 10 years ago. I changed course to investigate.

To my surprise I found a line of artillery deep in the centre of the city firing rounds into the air. The blasts were immense. Overpowering snaps cut through the sky as the howitzers fired, followed by the sound of rippling thunder as the explosions echoed off the skyscrapers nearby.

I didn’t have my recorder with me, however I vowed to return to capture these rare sounds and share them with sound editors and game audio designers. After all, it isn’t common to find or hear these guns, let alone to stumble upon a chance to record them.

After some research, I discovered that the guns were from the 7th Toronto Regiment of the Royal Canadian Army. I learned that they fired a 21-gun salute 3-4 times a year: Victoria Day, Canada Day, Remembrance Day, and others.

The unpredictable and uncontrollable had become an opportunity.

Why Record an Artillery Sound Library?

I returned many times to the firing site to record the artillery sounds. In 2015 I captured the first recordings and created the Battlefield Howitzer sound library. I returned again in 2017 to record more of these battlefield weapons.

The artillery sounds are quite rare. There are very few sound libraries of howitzers firing. They have so much power and character that it’s difficult to “fake it” or recreate them any other way.

The field pieces the 7th Regiment used were also a valuable mix of weapon types. They included the M101 C3 howitzers – a modified version of a popular US field piece used with dozens of operators worldwide since 1941. In addition, a rare British field gun, the Ordnance QF 25-pounder howitzer was also present. In service since 1940 and since retired, that weapon was used in many Commonwealth countries. Combined, it was an opportunity to share a global cross-section of late World War II field pieces that have been used in scores of conflicts up to the present day.

The recordings showcase an incredible soundscape. The jarring blast conveyed power. However the characteristic rumble was truly unique; it created a rare urban echo not typically heard in usual battlefield soundscapes. In addition, the rumble and “tails” of the explosions were very clean because of the tightly controlled environment. So, the pure recordings would offer helpful tools for sound design.

A second visit to the guns also produced flexible sound effects: perspectives, microphones, and sonic textures different than our first Battlefield Howitzer sound library.

Recording Artillery Sounds

So how did Airborne Sound record the howitzers? First let’s look at the challenges of recording artillery sound effects, then learn how they were overcome.

Artillery Recording Challenges

There are six especially tricky aspects to recording fireworks sounds:

1. Loud Artillery Sounds
   

   Artillery sounds are incredibly loud. Looking at the sound effects decibel level chart over on Creative Field Recording, it lists artillery fire at 150 decibels, and that’s at 500 feet (about 150 meters). I was planning to be closer than that, about 50 meters or so. Because of this, the sound risked being to be too loud for the equipment and damaging the recording.

   As mentioned in the How to Record Fireworks Sound FX post last month, few microphones can accommodate sounds that loud. In addition, the recording needed to capture both loud and soft sounds: the powerful snap as well as the relatively quieter rumble that followed.

   To get around this, we used line cuts and pads on the microphones and recorders. As a result, the microphones captured the full dynamic of the artillery from the loud blast to the cascading boom that followed.

2. Dealing with the Military

   It’s possible to create private recording sessions with the army. However, working with the military is difficult. It’s complicated and often cumbersome. Typically security clearances are needed, and that takes time. These sessions usually take place on a military base. That would convey a completely different sound than the urban rippling thunder heard in downtown Toronto.

   While the Canadian military is helpful to citizens, they are naturally quite strict when it comes to military matters. When I spoke with them, I found it was impossible to have any control over the firing of the guns, or to have any access to them in any way. That’s natural, of course. They are extremely dangerous weapons. And it was an event with a pre-planned agenda.

   This is a common situation for field recording. Many subjects are beyond a recordist’s power to predict or control. In this case, the best I could do was to flex one of a field recordists’s most powerful skills: adaptation. I learned the army’s rules and guidelines and worked within them.

3. Avoiding Crowds

   The guns were firing as part of a ceremony. That drew crowds. Of course, no one there cared about perfectly clean sound recordings. So, it was necessary to find a good location for the equipment that was as far from the chatting crowds as possible.

   

4. Restricted Movement

   Once the firing begins, a recordist becomes what I like to call “pinned down.” It’s difficult to change anything: the equipment, the settings, the positioning, or the guns themselves. Altering any of them would risk losing the extremely rare and limited performances.

   The workaround? It was essential to plan ahead. Knowing the rules and the location created the scope of work. Prepping equipment for extremely loud sounds ensured not a single shot would be lost.

   As a backup, multiple microphones were used in the event any of them failed.

5. Limited Gear Choices

   It would have been a dream to bring a multi-microphone set-up to capture the guns and the blasts from every conceivable perspective and distance. Within the scope of a military ceremony, bringing a full kit was impossible. In this case, it’s best to bring a light, flexible kit. We used a Neumann RSM 191-i recording to a Sound Devices 722 as the main microphone. That conveys rich texture and soundscape. A Sony PCM-D100 and a Sony PCM-D50 were additions that allowed ultra portable recording.

   

   

   

6. Only One Chance

   The 7th Regiment weren’t working for me. They were there for the ceremony. They would perform one 21-gun salute. There would be no repeats or do-overs. If batteries ran out or gear failed, the artillery wouldn’t stop to make up for my mistakes.

   Preparation and experience from the previous howitzer recording session helped. However it didn’t shake the knowledge that there was only one chance to get it right.

Technique for Recording Artillery Sounds

It may seem mundane, but the most important aspect of the shoot was preparation. After researching the 7th Regiment and some other fan websites, I found that the next performance would be on Victoria Day. I was flying back to Asia in a few months, and the next chance to record them would be Remembrance Day. So, there was only one chance to record the guns.

Prepping the gear was vital. From previous recordings, I had known how loud the blasts were. I had noted what settings were needed for the recorders and microphones. There were no practice shots available, of course, so this bit of knowledge ensured every blast would be captured perfectly.

I knew the location at Queen’s Park well. That didn’t guarantee that positioning would be easy. After all, ceremonies may block off certain areas. However, I was able to choose the best location in the half hour before the firing started – away from the crowd and on-axis to the guns. While being in noisy downtown Toronto, traffic was cordoned off so it wasn’t as much of a problem.

While it didn’t seem there was much I could control about the performance of the guns or the environment around me, I used the 4 P’s of field recording to adapt what I could: pick-up pattern, perspective, positioning, and patience. (Learn more about that technique on Creative Field Recording.)

The result? A complete set of clean recordings of M101 C3 howitzers and Ordnance QF 25-pounder artillery firing from three perspectives.

Mastering Artillery Sounds

What’s the best way to edit artillery sound effects?

Well, the bursts and explosions were so loud that they consumed any other sound. So, mastering aimed at cleaning or preserving the long rumble or “tails” after the initial explosions. After all, it’s the space that give character to gunshots and artillery fire. Luckily, the jarring aspect of the shots silenced the people and birds at first. However, some babies began crying and dogs began barking in the extreme distance. iZotope RX’s spectral repair took out the minute, pesky intrusions to ensure the rippling boom was completely clean.

All artillery shots were edited in tandem with the same length. The idea here was to provide options for sound designers so they could switch between the microphone for alternative sonic textures.

Artillery Sounds Bonus Mixes

As a bonus, I processed the raw tracks into two additional flavours:

• a “cinematic” mix. This sounds sharper, done to match the sound of the artillery in the Band of Brothers episode “Day of Days”. The concept was convey accuracy.
• a “thunder” mix with lots of bass and rumble to convey over-the-top power.

The processing was done with a mix of plug-ins including Softube’s Chandler Limited Germanium Compressor, Oxford TransMod, SPL Transient Designer Plus, and Soundtoys Decapitator. These transformed the raw effects into larger-than-life overpowering versions.

Artillery Sound Library Curation

The next step: organize and curate the artillery sounds. What’s the best way to describe such rare sound effects so that they are found and used?

Artillery Sounds Metadata

Getting the details correct was essential. For historical projects, it is vital to know exactly which guns and ammunition are being used. Weapon models often vary with sub-model types. Before the shoot I documented the types of guns with multiple photos.

Additional research helped accurately describe them with a precise name and model number. This was used to create a technical name with the type of gun, the action, microphone type, and any activity. This “scientific” name was paired with a human-friendly readable name. Extensive details were added to the metadata keywords to ensure the best, most accurate hits.

The result? 189 sounds (1 raw set with 2 processed versions) in nearly 900 megabytes of carefully recorded, edited, and curated artillery sounds.

Here’s a preview to the sound library:

Thanks for joining us for this artillery sound pack preview. Stay tuned! We will release the full collection next week. Join our free email newsletter to be notified when the sound library is available.

Update: the new sound library is now released! Click the button below for more info:

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