Creating Sound Effects

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Creating Sound Effects

The term sound effects can mean a wide variety of things. With regards to audio post-production, it refers to anything that could not be considered foley. This might be extensions of foley sounds, such as gunshots. The sound of the trigger being pulled or the gun being cocked would be considered a foley sound, whereas the sound of the gun being fired would be a sound effect. These sounds are also referred to as hard effects , and may come from a variety of sources including CD libraries, field recordings, studio recordings, and even synthesizers and other electronic sources. Often a combination of some or all of these possibilities will be used to create one sound effect.

Using Field Recordings

Field recordings can be the foundation for great sound effects. Going to the source for a desired sound effect is the most effective way of achieving realistic sounds. Junkyards can be great resources for sound effectsit's like having a gigantic foley pit with huge props.

Using Pro Tools on a laptop is a convenient way of recording in the field; it allows you to import files directly into your main Pro Tools rig for editing. Using the Mbox as an interface, you can create a system that is portable and can be operated by one person. Laptop cases are made that can be set up to hold your laptop in front of you while you're standing, allowing free movement while recording. The case shown in Figure 5.25 uses a special harness to hold the computer in front of you. The Mbox fits securely in the pouch and microphones can be held in your hands.

Figure 5.25. A laptop case that allows you to support the computer while walking freely and using your hands to aim microphones.


Unless a field recording is tailored to meet specific sound-effects requirements, some editing and processing may be needed to alter the length or pitch of the recording. Many times, layering of different sounds is used to create a single sound effect. Aspects of different sounds can be combined to create a complex and effective sound. For example, explosions are usually made up of several elements and can be created using many different sounds. The initial impact may come from an actual recording of an explosion layered with other percussive sounds, such as close-miked thuds on a floor, or even drums. Debris that is moved as a result of an explosion would also need to be layered in; the junkyard or foley stage can be a source for doing this. Fill a box up with all sorts of stuff, mixing different materials such as glass, metal, and wood. Find a slope steep enough to throw the material down, and record the sound it makes rolling down the hill. Edited into the impact sounds, this can create a dynamic and exciting sound for an explosion. The possible combinations are limitless.

Sometimes, however, realism is not the end goal, and you need to use other techniques to create fantastic sounds that are outside the realistic picture. Be creative and try sounds that are not so obvious. For example, crumpling tin foil, when pitched down an octave, can be a very interesting sound.

Sound Effects Libraries

For the budget-minded, pre-recorded sound effects libraries offer an easy-to-use resource for creation of sound effects. These libraries try to provide complete, ready-to-use sounds for many common effects used in post-production. Certain libraries might be tailored for specific types of productions , such as commercials with "zip-bys," sparkle sounds, standard footsteps, cars , clocks, doors, and so on. More specialized collections can be found for historical uses, with sounds from vintage vehicles, airplanes, and home appliances. Other libraries include wartime, natural, mechanical, human, automotive, avionic, and animal sounds.

A full-featured library such as the Hollywood Edge has varieties of almost every kind of sound imaginable. The initial cost of such a library can be rather large, but it may be possible to buy portions of the library over time, when each part is needed. While the cost of a library such as this can be considerable, creating a library from scratch can take years and cost quite a deal more in time spent. However, the result of a custom-built sound-effects library will be more original soundtracks. Overuse of pre-made libraries can lead to mundane soundtracks lacking in dynamics and interest.

One method of extending the use of an existing library is to apply processing to create new sounds. It is very common to use pitch changing and time stretching processing to create new sounds from the original library ones. Pitch-shifted versions can be layered with other sounds to create new and original sound effects, thereby extending the life of your library.

Whenever you create an original sound effect for a project, keep a copy for your own sound effects library. Over the years of working on many different projects you will amass a collection of unique sounds that you can call upon for your next project. The combination of original and library sounds should give you a large enough pallet to create unique soundscapes for your productions. Be sure to obtain any permission necessary to use original recordings made for a specific project. There might be copyright issues to deal with. Any legal rights to material generated by your work should be negotiated during pre-production. You don't want to get sued for using a sound effect that you created! Usually, sound effects by themselves do not fall under copyright laws, but there might be exceptions in certain cases.

Using Synthesizers and Samplers

Artificial creation of sound effects is a subject unto itself. The use of synthesizers and samplers to create unique sounds provides a whole universe of colors to paint with. The ability to generate tones, pitch samples, filter sounds, reverse audio, and audition these things on-the-fly gives you immediate feedback on how sounds will work in a particular setting.

Synthesizers

Anything that generates audio from electronic oscillators , small audio clips, acoustic modeling, or any combination of these can be considered a synthesizer . Pro Tools itself is a type of synthesizer. For our purposes, let's limit synthesizers to devices that are meant to create musical tones and that are controlled by a standard MIDI keyboard. These would include, but are not limited to, any type of electronic keyboard such as a Korg Wavestation or the Kurzweil K2000, shown in Figure 5.26.

Figure 5.26. The Kurzweill K2000 uses a combination of audio clips, oscillators, and filters to create musical sounds.


Today, many synths have migrated to the inside of the audio workstation. They have become computer programs themselves. It is possible to have a complete synthesizer with oscillators, filters, and envelopes that is a plug-in within Pro Tools. Access Virus , shown in Figure 5.27, is a good example of a plug-in or software synth.

Figure 5.27. The Access Virus virtual synthesizer is a plug-in that can be used inside of Pro Tools. It is played with an external MIDI controller.


Synthesizers can be used to enhance another sound effect. For instance, an explosion sound could be augmented by the use of a synthesizer playing a very low note that would, in essence, rumble like the sound of large chunks of debris falling to the ground. This subsonic enhancement could be layered with other explosion components to create a complete sound effect. By playing the sound on a keyboard, it is possible to audition different pitches of the tone in order to find one that compliments the other sounds the best. The ability to do this quickly makes the synthesizer a valuable tool to the sound designer.

Samplers

A sampler is a device capable of playing back audio files instantly when receiving MIDI information. When a certain key is pressed on a keyboard controller, the sampler will play the correlating audio file. Additionally, samplers are capable of playing one audio file, or sample, in several different musical pitches. You can take one recording of a flute playing a middle C and play it back as a D or an E in real time.

It would take much more time to accomplish the tasks common to a sampler inside of Pro Tools. Every time you wanted a new pitch to be played you would have to process the file in order to raise or lower the note. Samplers can do this to multiple samples at once with different pitches for each sample. Samplers can be used for sound design as well. Taking an explosion sound and placing it within a sampler will allow you to quickly hear that sound in many different pitches, both lower and higher. This can help make a sound fit the picture better.

Programming a group of footsteps recordings into a sampler can allow you to quickly play the footsteps while watching the video, as a foley artist would do. The ability to subtly alter the pitch of the footsteps can help keep variety in the soundtrack. Using traditional methods of editing each footstep into Pro Tools is much more time-consuming and tedious . Record the footsteps into a MIDI track first. Then edit the MIDI track if there are any timing errors before recording the samples into an audio track. Doing so can help conserve disk space.

Commonly used sound effects for a TV show could be placed in a sampler for quick access during spotting sessions. Each sound effect could be assigned to a key. This could allow you to spot a show on-the-fly, and come back to fine-tune each effect.

Samplers, such as the Kurzweil K2000, and software samplers, such as the Gigastudio shown in Figure 5.28, also make use of synthesizer-type filters to further modify the sound of the original samples. Envelope filters can be used to affect the attack and decay of sampled sounds, and LFOs (Low Frequency Oscillators) can modulate almost any parameter of the sampler as well.

Figure 5.28. Gigastudio sampler is a program that runs on a Windows computer and is capable of playing back 160 voices of samples. These samples are played back directly from the hard disk and are not limited in size or length to the amount of memory in the computer. This allows the use of longer, more realistic samples.


Even though Pro Tools itself is basically a gigantic sampler, dedicated sampling tools offer another method for sound manipulation that can prove much more efficient for certain tasks.

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PRO TOOLS R for video, film, and multimedia
PRO TOOLS R for video, film, and multimedia
ISBN: N/A
EAN: N/A
Year: 2003
Pages: 70

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