COMPOSITIONAL TECHNOLOGYWEEK 4

APPROACHES TO SONIC MATERIAL

PITCHA sonogram from sounds recorded in water near the North Pole. The trace opens with quiet background noise with a slowly descending unfocused high sound. There is a noisy percussive sound at around 0:15, and the high pitch continues to drop. This high phenomenon repeats and is joined by strongly harmonic ‘pitched’ note which continues through the rest of the trace slowly falling in frequency.

http://www.awi.de/fileadmin/user_upload/News/Feature_Stories/PALAOA/icesounds/mystic_sounds/sonogram.jpg

• The use of pitch is of fundamental importance to most types of music. Electroacoustic music is no exception. There are some important differences to the way that we understand and use pitch, largely due to the unique set of tools available in the studio.

• Most western music is dominated by the idea of notes and rhythms. Pitch and duration are easily quantifiable either in conversation or notation by the regular division and codification of these parameters. With Electroacoustic music we are free to experiment with a more holistic continuous understanding.

At a given time a sound can be quantified and defined by its pitch, volume, and timbre. This is taking a snapshot, so disregards issues such as duration, relative loudness and harmonicity. Pitch, volume and timbre can be thought of as a 3 dimensional space in which a sound could be plotted. In the case of clearly defined ‘notated’ music there are a number of set possibilities e.g. the chromatic scale, pp-ff and orchestral instruments. Looking at the Rubik’s Cube analogy these sounds would be occupying the black lines of the potential space. With electronic control and the loss of the need to define the space to the performer we are free to use the entire pitch volume timbre space as a continuum. Thus Acousmatic music rarely uses ‘notes’ and ‘harmony’ in the traditional sense, as it is one of the few musical forms that does not necessarily have to!

• Our understanding of pitch is quite complex. Fundamentally our notion of the pitch of an object is based on the frequency at which it is vibrating. If we were to hear an object vibrating at 440Hz it would be what describe as an A, as that pitch doubles (to 880Hz) we go up an octave and if it were to half (to 220Hz) we descend by an octave.

• This is very simple in the case of clear sounds such as a sine wave, however some are more complex. The Sonogram trace on the first page shows a number of sounds running simultaneously. The most striking is the long harmonic sound with the ‘radiator’ pattern of regular harmonics. In this case the note that we would hear as the ‘pitch’ is the lowest and loudest harmonic (the 1st, or fundamental harmonic). However in the case of bells and other less harmonically ordered sounds there is no definite centred pitch but rather a series of harmonics that come to the fore at different points over time.

• Timbre or spectrum can be thought of in the following way, this then feeds into our idea of pitch.

• Timbre or spectrum can be thought of in the following way, this then feeds into our idea of pitch.

 

Pitched

 

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Stable Unstable

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Noisy

• In addition to this pitch can then be broken down with the following space:

Static Quantised

 

 

 

 

Continuous Dynamic

• Common methods of the use of pitch

• Correspondence

This is achieved when a number of sounds share a large amount of the same pitch based material. One sound can feel connected to another if it is heard in quick succession at the same pitch. This can even be true with strongly related pitches such as at half the frequency. Correspondence, or lack of it, can often be the reason why sounds do or don’t feel like they ‘go together’. Quite often to achieve this you will need to pitch or time-shift some material to obtain pitch similarities.

• Colouration

This is where largely un-pitched (or noise-based) sounds are processed in order to bring out specific frequencies. This can be done with tools such as: EQ, de-noising, or even extreme gating. This can result in a large variety of effects and forms some of the basis of subtractive synthesis.

• Aggregates

A pitch aggregate is simply a collection of pitches at the same time, rather like a less specific version of the term ‘chord’. Where the excitement comes is the very large grey area between an aggregate made from a number of sources (effectively a noisy chord) and a solo in-harmonic structure. Complex evolving tones and gestures can be easily built up this way, with the potential for transformation of sound and meaning thrown in.

• Definition

The use of pitch can bring clarity to ideas, by centring them at different points in the continuum.

• Gesture

Pitch can be a powerful tool for creating gesture. Glissando is massively useful, as is the use of disjointed pitch transformations. These gestural events can be applied to individual objects, or indeed entire passages of music.

• Structure

At a larger scale, pitch can be very useful for defining structure. A section may consist largely of low sounds or in the case of two different subjects one may consist only of midrange sounds whilst the other may be constructed solely of high and low material.

• Systems

There is nothing wrong with using sounds and structures that refer to established pitch systems such as modality or the tempered scale. Within the language of electrnic music it is often a very powerful statement to opt for the simplicity of such systems. However do not over-do it, keep things evolving and interesting.

SPACE

• Space and historical precedent

• We exist in a spatial environment and our understanding of it is important to our day to day survival. Space is an innate part of our understanding of most music, even if we are not always aware of it. Listening to a symphony orchestra or any ensemble is an innately spatial experience; the composition is diffused based on a complex set of rules. These are governed by a pool of possible pitch, duration volume and timbre choices. More simply the music is placed throughout the ensemble based on the instruments performing it (consider the motion of left to right and treble to bass in a conventionally arranged string section). Historically there are examples of music such as Gabrielli’s use of separated choirs that make use of space as an overt parameter, but it is since the rise of electronic music that this has become more widespread.

• Recording

Before even opening any audio editing software we can make choices about the stereo information contained in our recordings. Microphones can be positioned to capture a wider or narrower stereo spread and sound can be captured stationary or from an object in motion.

• Towards a classification of stereo space

Stereo is created by the use of 2 discrete audio channels however we can create far more than this simple 2 channel set-up would suggest.

• We have 3 possible planes of spatialization for a given sound:

Horizontal plane (simple left/right balance based largely on amplitude)

Virtual plane (depth, created by psycho-acoustic effects employing processes such as reverb and EQ)

Implied plane (height, largely created by frequency and the construct of ‘low and high’ sounds)

• In addition to this we have 2 basic states of a sound object within that space:

Static

Dynamic (movement of a sound in one or more plane)

• At a higher level of classification we have concepts such as the predictable motion of a sound within space, moving in a spiral for instance. It is also possible to then consider the interaction of sound objects with each other in the stereo space, as well as the linking of spatial motion to implied musical gesture, however we will focus on the lower level concepts initially.

• No matter how complex they are to describe, every sound has pitch timbre and volume characteristics. They also have a place within the stereo field whether you have specifically defined one or not. After all if you can hear it, it must come from somewhere!

Horizontal placement

• Horizontal placement can be measured physically by comparing the loudness of one channel to the other, in this sense it is a ‘real’ parameter.

• Do not pan anything absolutely left or absolutely right. This will result in the stereo image of the recorded sound being flattened to mono and the sound having no presence in the opposite speaker.

• Try to use the full available width of the stereo field.

• Ensure that your mix does not become lop-sided. It should balance in the middle not favouring either the left/right extremes and not having holes in it by favouring either the centre or the edges.

• Movement is very easy in the horizontal plane. Simply pan it.

• Different positions in the left/right plane are useful for defining different sounds and ideas. However it is worth remembering that our perception space is not as accurate as you would be lead to believe by programs such as Pro Tools.

Virtual placement

• An impression of depth can be created by:

NEAR FAR

Loud Quiet

Less reverb More reverb

No EQ More EQ (incl. less HF)

Don’t place sounds too far back or with too much reverb for too long as it will tend to be lost. Also, most performance spaces have their own reverb so you don’t need to add in too much.

Implied placement

• The concept of ‘high and low’ sounds as analogous to frequency is almost culturally universal. As well as this bass sounds can be more easily physically experienced transmitted through the floor conversely high frequency sounds less so.

• Frequency differences can help to define different ideas.

• Many low frequency sounds contain high frequency harmonics so a low pitched sound does not necessarily mean that it is exclusively placed low in the implied space.

• To create specifically low sounds it may be necessary to use a filter to remove higher partials.

• Just as with the virtual and horizontal planes motion though such as glissando can be very effective, providing it is not over used.

Combinations

• Obviously this is simply a breakdown of the available parameters. Combinations of movement can be used to great effect and form a part of what defines the overall genre of acousmatic music. They can also be good fun.

TEXTURE• Texture is a fundamental part of the way we

understand music. In conventional music, texture is often thought of as a function of a number of factors, mainly; harmony/polyphony, rhythm and orchestration. In a sense this holds true for acousmatic music, in that texture is the comprehension of changes in the music over time. These changes can be in pitch, volume or timbre and can be relative to other parts of the piece or relative to our expectations of a work.

Cordierite hornfels at, Caldew River, Carrock Fell, Lake District, England. Keele collection. http://hypocentre.posterous.com

• Texture is not really a continuous parameter such as pitch, although the objects it describes can be seen as such. In everyday usage ‘texture’ or ‘textured’ usually refers to sound objects or structures with a lot of changing internal information or perceptible internal detail. These are what we would commonly call ‘course’ or ‘rough’ textures. Obviously the term texture can also refer to smooth textures, although this link is not as strong, in that when we describe something as textured we tend to think of something ‘at least slightly bumpy’.

Rough Smooth

Textured (no discernable texture?)

Creating and controlling texture

• Like a lot of other musical parameters texture can be both static and dynamic in that it can either evolve or not. This can be thought of at two different levels those of the quantum (individual elements of texture) and global level. Where texture becomes special is that it is a sophisticated combination of a variety of factors such as pitch, volume and spatial information

Quantum characteristics PitchVolumeLengthPanningTimbrePanning

Global characteristics

 DensityFocusPitchVolumeTimbrePanningTrajectory (evolution of the above)

Quantum level control

• There are two main methods of creating texture additive and divisive:

Additive texture.

• This is where different sounds are brought together to form a larger cohesive entity. This can be achieved by a variety of different methods

• Mixing – Quite simply adding lots of sounds into the mix and balancing them as required if this is done on a large enough scale the tendency is to stop perceiving individual sounds and focus on the overall cloud

• Sampler sequences – Loading sound objects into a sampling system that can then trigger them. This is useful in that gestures can be repeated and modified relatively easily. In addition to this most samplers offer control over pitch and speed of playback which can add further detail.

• Granular Synthesis – In granular synthesis sound is dived into small grains typically between 1-100ms, although longer may be required for specifically textural effects. These can be mixed with grains from other sound sources to create new sounds and textures.

The tendency at first is to notice the overall flock and its shape, not individual birds. http://en.wikipedia.org/wiki/Flock_%28birds%29

Divisive Texture.

• These methods start with smoother sounds and break them up in some way.

• Cut and splice - editing to create discontinuities. This is highly effective but can be very labour intensive if working with large amounts of material.

• Convolution- Using 2 (or more) sounds to interact, thus creating the potential for twice as much detail at one time.

• Gating - Use of gating to only have the louder portions of a sound

• Shuffling – A technique that is very useful with purpose built GRM plug-ins.

• Global level control

• In many cases textures can be thought of as a single element or sound. As such they can be used and handled as a single sound object, as well as being regarded as a composite of many different elements. Many automated processes such as shuffling, granular synthesis or sample based procedures can offer levels of control over the global output such as density, pitch or focus.

• Textures can be built up and dismantled relatively easily from their constituent parts. Specific ‘bounced’ textures can also be layered and mixed together. In addition to this all of the processing that is available with a single sound object (such as filtering, pitch shift, gating etc.) is available for a single bounced texture, thus it is possible to shape the overall result.

• Using textures

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• The ease with which textures can be created often leads to their overuse. They should be approached with caution as the volume of detail can become fatiguing very quickly and lead to passive listening and boredom. They are also sometimes hard to justify musically in that starting and stopping a texture is often a lot more problematic than keeping it going or not starting at all.

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• Potential uses:

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• Variation and development of objects and structures

• Interaction of objects and structures

• Rhythmic interest

• Background detail

• Screening (partial masking or obscuring)

• Masking

ARTICULATION

• In music articulation refers to the way sounds are distinguished from, or connected to each other. Articulation can refer to the way that individual notes are played such as staccato or how sections are joined together to create musical flow. Articulation comes from the Latin articulare meaning ‘to joint’ and in music refers to the way that ideas interrelate in time.

Articulation

Seamless Disjointed

Causality: Joining sounds in time. One of the most puzzling and frustrating parts of acousmatic composition can be making the transition from one sound or event to the next. Quite simply, how to join them?The problem is often one of cause and effect. Within the computer may physical laws are put on hold, we can easily have the sound of a paper burning underwater for instance. Unfortunately many times our brains will not entirely let us forget simple real world issues.Consider the cartoon frame. To break down what we are actually perceiving here could take an awfully long time, but suffice it to say that with a mixture of culture, common sense and several million years of evolving we see that there is a (not very realistic) representation of a coyote and a bird. The bird appears to be gloating and the Coyote appears to be in want of terra firma. From the visual and cultural context we instantly know he is falling we might even guess the sound he may be making, it would be hard to imagine much else without outside intervention e.g. a very large eagle. In electroacoustic music it is quite possible to make one sound follow on from another for no obvious reason and that is fine providing that is acceptable. Sometimes it simply stops the music from making sense, so here are a few ways to get around this.

• Recording

• In order to make your sounds feel more ‘real’ consider how you are capturing them. It is quite possible to record sound objects by taking samples from the real world. It can be very useful to take extended phrases, a performance on the sound object in a real world sense, as this can provide a very tangible reality when played back.

• Anacrusis

• The term anacrusis is taken from conventional music and refers to an up-beat preparation to a down-beat. In electroacoustic music it refers to anything that sets up the expectation of a following event, this can function on a number of levels and is not strictly a rhythmic element as the name would suggest the chord progression IIb7 V7... has the same effect in western harmony. Some simple methods of creating anacruses are:

• Dynamic. A rapidly rising crescendo can be a compelling lead into an event. This often works better if issues of ‘loudness’ (contextual volume and timbre etc.) are addressed rather than simply turning the volume up.

• Pitch: Swift glissandi can imply motion towards or away from something.

• Referential: In the case of real world objects often one sound may be expected to follow another e.g. a squeaky door closing could be followed by the bang of it shutting.

• Repetition: A simple way to create expectation is to have done something before

• 3 Card Trick

• The three card trick builds upon the idea of repetition. Our brains like to find and predict patterns. When we hear an event and then hear it repeated we tend to assume it may happen again. When this does happen this expectation is fulfilled and there is a sense of ‘round off’ to the pattern. New material introduced with the third repetition also often fits.

Overlapping

• Overlapping is as simple as the name would suggest. Sometimes all that is required is to fade a new piece of material in. There are subtle variations on this technique such as running the new material at a very low volume level under the old before bringing the old material to a conclusion. This leads to a sense that the new material was always there even if the listener did not know it.

Punching and Distraction

• Punching and distraction are two less subtle ways of articulating material, but they basically rely on a similar set of phenomena.

• Punching: Quite simply putting a loud and noisy event over a difficult join between two or more elements. This can be very effective for marking changes in material or section and potentially very useful for rhythm if the punch object is part of a wider rhythmic framework.

• Distraction: This is what is says. The listeners’ attention can be drawn away from difficult technical elements by simply doing something else ‘flashy’ at the same time, in much the same way as a magic trick.

MONTAGE

• Montage, Mixage, Filtrage

• In the early days of musique concrete, there were two main techniques, those of; mixage (mixing or layering of sounds) and montage (putting sounds together in sequences). Intrisically adding sounds ontop of, or beside, each other. Only later did the idea of filtrage (changing sounds) really take off. This was partly due to the technical difficulties of transforming sounds in those early days, and today it is one of the main methods used in acousmatic composition. Today mixing and processing are comparitively easy with programs such as Pro Tools. Montage tends to be neglected as it is less glamourous than using new pieces of software and often involves more work than mixage and filtrage. Montage may refer to the simple act of arranging or composing sounds along a timeline, it may also refer to the interactions of these sounds, a particularly noticable fast cutting of objects often being refered to as ‘a montage’, when in truth it exists all thr way through the work in one form or another. In its strictest form montage is a purely horizontal phenomenom as sounds are executed one after the other as opposed to mixage where sounds are layered ‘on top of’ each other.

• There are a number of ways that montage can be used:

(Un)reality

• Montage can be a powerful tool for creating environments and virtual spaces. These can be realistic such as a recording of a room full of people talking followed by the opening and closing of a door into the sound of a spring day. Equally we create impossible justapositions such as opening the door in the previous example into the sound of the internal workings of a pocket watch.

Poetry and metaphor

• Part of the real excitement of acousmatic and electroacoustic composition is the use of real world sounds and making use of some of the connotations they may have. With the placement of sounds in time it is possible to create a wealth of complex meanings based not only on their actual sounds but also based on what they symbolise for the listener.

Developing rhymic material

• Most music requires at least some rhythmic material. This does not necessarily mean beat-locked repetitive material. A repetitive beat is simply one (very specific) kind of rhythm there are many others that we may be trying to bring out. For example a crackling fire is rhythmically very beautiful, but is not at all repetitive.

• Through montage we have control over rhythm in two ways. The first is in our choice of sound. Every sound has its own internal rhythm, based on factors such as its texture, pitch and amplitude envelope, the specific sounds we trigger will have an effect on the rhythm and pacing of the music. The second element of control builds on this, in that we then have control over when these sounds are triggered. An effective rhythmic montage will often use the ‘natural’ rhythm of the sounds and assemble them into a larger rhythmic sturcture.

• Heirachical

• It is easy to think of processing or mixing as something you apply to a sound object and placement in time as rather arbitrary and the first thing to do in order to get onto the interesting work. If we redress the balance of montage, mixage, and filtrage and view them as 3 equal disciplines or indeed as being in descending order of importance we gain a different perspective on composition. This gives rise to ideas such as; processing different versions of a sound and then creating a timeline or montage as if they were original sounds, or using mixage to create new objects which are then bounced and arranged into a composed track.

• Creation of new timbre/synthesis

• Montage can also be used to create new timbre. Carefully splicing the attack portion of one sound to the resonant portion of another can give rise to strikingly ‘new’ sounds. This relies upon the fact that most of the information we use to characterise a sound in terms of what it is is contained in the first few milliseconds. By working carefully we can create some very unusual objects.

Context

• Montage is essentially the judgement of the timing of sounds. Therefore we can use it to create different contexts around a given object. A sound may be very quiet and muddy in the context of a large amount of loud bright material, but may in turn appear very loud and bright in the middle of very delicate sounds. The key is variety and judgement.

Practicalities

• Montage is very powerful. It does take time and effort so here are a few tricks to speed things up!

• Firstly practice editing, a really powerful montage can be the result of hours of editing a couple of seconds saved per edit will add up.

• Take a long stretch of material and cut another smaller piece into the middle of it, repeat with another smaller piece in a different place and so on into smaller and smaller units, then listen and audition it.

• Go random. Take a few layers of material that have lots of slience in and play them at the same time, then adjust as required and pick out the good bits (if any).

PICK A SUBMISSION FORMAT, OR DEVISE YOUR OWN AND GET IT CHECKED OUT THEN GET ON WITH IT 1. Submission of a portfolio of 3 stereo tracks totalling approximately 8 mins,

comprising music made from entirely found sounds and processed sound objects.

2. Submission of a portfolio of 3 stereo tracks totalling approximately 8 mins, comprising music made from synthesised sounds.

3. A 3 minute demonstration of your own digital instrument built in Max controlled using live triggering of your own sampled and processed audio.

4. A 4 minute demonstration of your own digital instrument built in Max controlled over by iPhone touch screen over OSC.

5. Generation of an 8 minute notated score by algorithmic methods

6. A sound installation work capable of sustaining interest for a minimum of 8 minutes.