In the Beginning, There Was Film...
The romantic notion of sound design is what gets a lot people into film and game sound; that idea of creating sounds that no one has heard before and making a visual element become alive is a pursuit which is almost archetypical. The key concept which dominates the endeavor is “emotional impact.” We want our creations to have an innate relevance to the actions which we hope to attach them to.
Allow me to introduce myself. My name is Charles Maynes, I am a sound designer and recordist of sound effects for both feature films and video games. I specialize in military related subjects, so I am around weapons and other military gear more than most people in my field.
As to the design philosophies, the principal difference between a game experience and a film is that the film does not repeat itself. It is told in a linear narrative and can get away with a more exaggerated application of sound. A wonderful example of this is the film Dirty Harry, which set the standard for cinematic gunshot sounds for decades.
In the game experience though, we are dealing with scenarios that are far less linear in most cases, and in a FPS type game, the idea of a “towering” action sound would grow tiring in very short order. This of course does not diminish the absolute requirement for the sound to be interesting and, again, emotionally satisfying.
How We Got There
In the case of the action/adventure/war game, we are presented with some interesting quandaries. First, most playing these games have no direct reference to what battle sounds like; they only have the reference of what they have seen in film, television or other games. They are relying on us professionals to create a believable and exciting world for their entertainment (or in some cases, training). We are also contending with the general lack of experience, in these sorts of venues, of the people who are constructing the presentation.
So, in effect it can be a sort of crazy game of “telephone” in communicating these ideas. In effect, it is as if someone was trying to learn surgery by reading Mary Shelley’s Frankenstein. This is not a bad thing, but if a new and more realistic expression of the battle experience is desired, this is not an easy way to get there.
As I mentioned earlier, I specialize in military subjects, and have henceforth been involved in recording and designing these sorts of sounds for a number of different films and games. I try to take a holistic approach to the process; I have always made it a point for the audio team to be able to experience firing the weapons which were being recorded, so that they will have a practical reference to how these actually feel and emotionally register in real life, and so they can have a point of reference to bring this to the end user - the game player.
In the game milieu, it seems that bigger is also more desirable, but we rapidly run out of headroom to accommodate the most “stupendous” of events. So in this case, we have to find a way to proportionally scale the conceptual presentation of, say, a weapon, or family of weapons, so that again we can give the desired “emotional” experience.
Not all guns sound the same, and they can certainly vary in their calibers, but they are all plenty dramatic when the weapon is in your hands and firing. There are also characteristics present in a lot of weapons which provide unique qualities. Other sounds, like explosions, present challenges as well, the biggest being the containment of the sound energy, which eclipses the capabilities of all sound recording technologies presently available. Devices like “flash bang” grenades have a dynamic range that goes out to about 180db, which exceeds 24 bit recording systems by about 20db.
If during the recording process we set levels and attenuation to be able to capture the maximum loudness of the sound, we will leave the field with something that, upon review, will seem very unsatisfying. This is due to the fact that the amount of time that maximum level is present is but a tiny, tiny fraction of the overall duration of the sound event. So we tend to strike a balance between using dynamic range compression and even distortion to mimic the way our ears and brain take that sound in.
All of this to the game audio person may seem extremely obvious, but I have heard so many gun recordings that sound like popcorn. It saddens my heart. The costs involved in even the most modest of weapons recording sessions are such that to walk away with source that is so far detached from what most people want to see as an end product is something that is difficult to defend from a financial point of view.
For the most part guns sound pretty similar, so I like to use this analogy when describing the contribution of the location: if we were to listen to electric guitars being played without amplification, it would be VERY difficult to tell one from another (this would be the role of the gun).
Now if we plug the guitars into amplifiers, the differences will generally be much greater, because of the way the pickups interact with the amp, with all of it being controlled by the player. And since it is much louder, the acoustic space provides a significant signature. And reverberant spaces can really enhance the “bigness” of the sound.
So with all that behind us, we can get into some techniques to get cool sounds. Doing a gun recording session is an expensive enterprise. When recording anything, we hopefully go out into the field with a good collection of tools so that we can get what we need. The basic breakdown of field gear falls into the following categories: Recorders, Mixer/Pre-Amps, Microphones, Power, and Cabling.
I will always try to bring as many channels of recorders out that I can, usually between 8 and 14 tracks worth. The other thing I feel strongly about is recording at the highest practical resolution available. Most stuff I do at 96k/24bit resolution. Though it will likely never be used by an end user at this resolution, it gives a much more life-like sound to my ears.
Mixers / Pre-amps
Many of the current recorders available have good quality microphone pre-amps, but in some cases having an outboard mixer or pre-amp is a requirement. Again, since our “talent” is an expensive and loud character, it makes sense to have good gear to capture them with the least amount of unwanted distortion possible. Companies like Sound Devices, Sonosax and Cooper make very good sounding mixers and pre-amps. They are expensive, but they are generally available for rent in most big cities.
This is one of my favorite topics. Guns and explosions are one of the great ways to learn about translating the physical to the electrical. The many different types of microphones all respond quite differently to really loud sounds and will impart their signature on the recording in a very substantial way. The types of microphones I find most useful are Dynamic, Condenser, Boundary (PZM), Contact...well, just about all of them, actually.
The biggest trick in the process is finding the optimum distance from the sound source. This, I know, is shamefully obvious, but it is worth saying. One really important reason for this is that when recording something like a weapon or explosion occurring, the physical shock-wave is going to be very misleading while you are listening in on your headphones. It is quite important to carefully review your recordings so that you are REALLY getting the sound you think you are. Again, you will need to carefully determine your sound source and its location, and then try to use the best microphone to capture it. With a big sound like these, the best sound location may in fact be a reflection from a nearby building or hill, so you want to make sure you have some channels getting that sound.
Another key factor is that some microphones do very interesting things when they become overwhelmed with sound pressure. A lot of that very nicely models the way our ears work as well - Condenser and PZM can almost “fold back” on themselves as the diaphragm reaches the end of its travel. I personally find this to be a pleasing effect, and will try to get it every chance I get.
The original expressions of this effect were realized with the hallowed Nagra IV recorder with Schoeps CMC condenser mics. Many people feel that the Nagra delivers the best sound for guns, but I think this effect was more caused by the reactions between the mics and Nagra mic pre-amplifier. Yet another consideration is the physics of how fast sound travels; if you want to get a rich low-end in the sound, you will need to have microphone further away from the weapon.
The Fast Gun Template
On the sessions I do, I am using a template which is generally a pretty good starting point- this is designed around having 8 channels of recorders.
Start with a stereo pair of dynamic mics basically arranged in an equilateral triangle from the weapon, with the two mics in front, and pointing to the weapons muzzle. Try to have about a 8- to 12-foot distance here, but it may vary further depending on the gun itself.
A second stereo pair condenser mics in an x/y pattern. Try putting about 10 to 12 feet behind the weapon. These are elevated also to about 7 feet. Do some test firing, sometimes you will shift the whole setup and sometimes change the directions the mics are pointing for a better sound.
Again a stereo pair, this time a Crown SASS stereo PZM mic. Place the mic setup about 30 feet behind the weapon. This mic captures a very nice low end from most weapons
Start with a shotgun mic set up on the right side of the weapon, just over the shoulder of the shooter. For the second channel, a Lavaliere can be attached to the weapon or the person shooting the weapon.
Between all of the them you can usually dial in a pretty good variety of sound pretty quickly.
For larger setups, you may have more distant mics to catch a more reverberant quality or potentially mics set up near the impact area to get the sound of the bullets passing by.
So with all this, you go out and record a bunch of guns. What now?
Well, the first thing you will notice when you get back to the sound department is that the stuff, if it is not horribly distorted due to inattention, is going to seem a lot quieter than the way it seemed on the range. This is of course due to the loudness of the source; guns are pretty loud. So you will want to first be in a position to review the material at perhaps a louder volume than you might normally work at to see if the character of the experience was captured. If so, then the work will be a LOT easier. This is all a bit like cooking; the better the ingredients, the better the meal. Once you identify the useful channels, you can move into the work of making it sound that great at a much lower volume.
Compression and Ways To Do It
A compressor is a device or plugin which narrows the dynamic range of incoming audio. It will attempt to push-up (via it’s make-up gain) the lower level information, while it also is reducing the strongest moments of the incoming audio. It has a threshold control which will determine the area of signal amplitude it process. There is also a control for the “knee,” which is essentially how severe the peaks of the loud audio is going to be let through the processor.
Some compressors have unique curves which might be useful for special effects, where the amplitude range of the signal can arbitrarily attenuated. Much more time could be spent discussing types of compressors and their merits
A close cousin to compression: basically, limiting is a simpler version of compression. The main purpose is to control peaks in the program material. There will tend to be threshold control which will determine when the limiter will affect the signal, and there is usually a makeup gain control. Limiters can be set to smash the audio pretty good, causing distortion as well. Whether the distortion is artful is of course a subjective issue.
A la the SPL Fatso or plugins such as the McDSP plugin “Analog Channel,” which models analog tape compression. The Nagra IV was mentioned earlier as a revered machine to capture sound effects with. These plugins and devices attempt mimic the way analog tale would provide compression to a signal.
Tube electronics can add subtle harmonic distortion which, to use a popular phrase, “warms up” a digital recording, making it sound more “analog.” What happens with both of these effects is that the transient “edges,” which are difficult for some speakers to reproduce, are smoothed out so the sound quality might be less sharp, and more pleasing to the ear. There are software tools for this as well
Distortion is just that, it is the signal getting mangled by a the effects of overdriving the circuits it is traveling through. Many times, distortion implies danger and out of control loudness - useful characters for something like a gunshot or explosion!
To accomplish this effect there are many choices, in forms ranging from guitar-oriented distortion boxes to plugins like the Sony “Inflator,” which adds varying amounts of distortion to give the impression of greater volume. Waveshaping plugins also fall in to this category of treatment.
Other Dynamic Treatments
Expansion can sometimes come in handy if you are dealing with sounds that are unwanted, but the sound you want is living there too. Basically, an expander is the opposite of a compressor. There are many different plugins and hardware boxes that are available, and their basic use is to minimize low amplitude sound. A lot of times they can be useful for reducing the amount of reverb or ambience that might be in your source recordings.
Multi-Band Dynamics Processing
These, which are available as both hardware devices as well as computer plugins are extremely powerful, in the manner which they really can allow a very fine control of frequency ranges to be processed independently. An example would be applying limiting to the lower frequency range of a recording, with the higher frequencies expanded in order tighten up the ambience of the recording. Some examples of plugins for this would be the McDSP ML4000, the TC Master X, and Waves C4.
The final part of the journey is assembling the components for your final sound. In many cases, you might end up with a number of audio tracks which make up your end sound. These could start with a good recording on a given weapon, then have a mechanism layer which might allow the metallic sounds of the device to be brought forward, followed by low and high elements which are added to taste, and possibly a layer which is a natural ambience.
Any sound that is going to be a “featured” sound -- in other words, a sound that is not a part of the background -- will likely require a a number elements, which in many cases will be quite musical in their character; the idea of a Low-Mid-High frequency division. Sometimes in the course of putting together your sound, it will be easy to over-emphasize one aspect of the sound over others - perhaps the clatter of the weapon, or the debris which might be thrown from the explosion.
All I can say about this is that this is the end of this article, and your artistic license gets to take it from here.