Sonic Art & Sound Design- P17 pdf

Thus we discover much about their nature and meaning: it is rarely sufficient to present a sound ‘as is’ since this tells us only what is on the surface, not what the sound is made of at

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Job no : 76098 Title : The Fundamentals Of Sonic Art Client : AVA

Scn : #150 Size : 200(w)230(h)mm Co : M3 C0 (All To Spot)(Coagl)

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Articulation

One of the most fundamental activities of sonic art involves examining individual sounds to see what they are made of and what they relate to Thus we discover much about their nature and meaning: it

is rarely sufficient to present a sound ‘as is’ since this tells us only what is on the surface, not what the sound is made of at

a deeper level or what its relationships may be

Before we examine the context in which

we hear a sound, we need to consider how

to discover its structure and there is no better way of doing this than identifying its components and seeing how best to display them This is known as articulation and we can approach it in two main ways:

firstly, we can be analytical and uncover the components that make up a sound object and, secondly, we can use another sound as a means of discovering how it interacts with others

PROCESS AND PRACTICE

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Right: The Behringer Multigate Pro

A simple dynamics controller capable

of a useful range of processes.

Image used with permission of BEHRINGER International GmbH

International GmbH.

Both approaches help us to understand what our sound consists of and what it may signify: both can be undertaken using regular studio technologies A number of possible processes could be adopted: for example the filter of a synthesiser allows us to isolate and hear each individual harmonic Here we consider two other examples: the (noise) gate and the vocoder

For our purposes, the gate is the most useful of the several types of dynamic processor One quality is common to all: the level of sound passing through the unit

is subject to automatic control This is usually derived from the sound itself or via a ‘side chain’ carrying the same information However, there is no reason why this has to be so: the controlling element can be derived from another source so that one sound is subject to the ‘articulation’ of another

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STUDIO OR LABORATORY?

input

control input from incoming signal

gain control output

input gain control output

control input from external source

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Left: Simple dynamics processor

The incoming signal directly provides information used to control the level of the output.

Left: Dynamics processor with side chain

The information used to control the level of the output normally comes from the incoming signal but can be derived from another source allowing the dynamics of one sound to be imposed upon another.

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insrument (carrier)

bandpass

envelope followers

bandpass filters mic or drums

(modulator)

vocoder allows one sound (the carrier) to

be articulated by another (the modulator) but there the resemblance ends: the vocoder takes the modulator signal and analyses it for energy at different frequencies It takes this information and applies it to filters and envelope followers that act upon the carrier as shown in the diagram

Traditionally, the vocoder encodes the human voice upon something else, usually resulting in crudely ‘singing’ synthesisers.7

A little imagination will suggest that this approach can be far more versatile: it can encode any sound upon any other – arguably the ultimate in articulation

A gate usually passes no signal unless its

volume exceeds a set level In normal use,

it is our chosen sound that opens and

closes the gate for itself but we can use

another sound for this purpose: applying

our second sound to the side chain will

open and close the gate independent of

our original sound thereby articulating

one sound by another.6This can tell us a

great deal about the dynamic structure of

both sounds

The gate offers a useful form of

articulation but works very simply upon

sounds as a whole A more sophisticated

(although essentially similar) approach is

offered by a vocoder Like the gate, the

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Left: Diagram of a vocoder

Vocoders allow one sound (the carrier) to be articulated by another (the modulator).Unlike dynamics processors, vocoders analyse energy levels at a number

of frequencies in the modulator signal and apply the results to equivalent frequency bands in the carrier signal.

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6 A particularly good example of this

occurs on the track Fire on the 1977

album Consequences by Kevin Godley

and Lol Creme Here, the cracklings

and poppings of a fire are used to

trigger a noise gate that is carrying a

vocal track singing the word ‘fire’.

Hence the word, with all the meaning

that it has for us, is apparently

articulated by the sound of the actual

fire itself.

7 There are other means by which

instruments and other sound sources

may be made to speak or sing A

simple approach plays the sound back

through Walkman earpieces or via a

tube, both of which are placed in the

mouth The user then shapes the

desired words or sounds silently and

his/her vocal track takes on the

function of a (rather limited) vocoder.

Other approaches include using

transducers to artificially excite the

vocal chords Most famously used to

create Sparky’s Magic Piano, these are

also used to provide an alternative to

natural speech for patients who have

undergone surgery on their larynx.

STUDIO OR LABORATORY?

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Above, top: Software vocoder

This software vocoder is made by Propellerheads.

Image courtesy of Propellerhead Software AB.

Above: Altiverb

A hardware or software reverberation system using convolution processing to impose a sampled acoustic upon the incoming sound.

Image courtesy of Audio Ease.

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Space and place

Having created a sound, we need to

present it Conventional studio practice

takes very little notice of this beyond

adding a little treatment and

reverberation (see also pp.36–37) This

denies us a useful opportunity – that of

hearing our sound in relation to a real or

imaginary environment; placing a sound in

an acoustic space can do much to

reinforce or contrast with our

expectations

The basic technique here is reverberation:

many systems exist that simulate real and

imaginary environments and the best of

these are capable of excellent

performance Where many fall short is

that they create ‘spaces’ that are

impossible or unbelievable and, whilst

these are immediately attractive, their

artificiality may make them unsatisfying

in the longer term

The space in which a sound is performed

and heard can dramatically influence the

way in which we perceive and respond to

it,8hence the need for spaces to be

believable Rather than attempting to simulate the acoustics of a real space, convolution allows us to sample the actual qualities of a space and to use them as a matrix in which to embed our sound Thus

it is possible to place a sound in the acoustic of London’s Albert Hall or the dome of the Taj Mahal Convolution systems find wide application not least since one can make a location recording

of a chosen acoustic space and can then

‘place’ one’s own sounds in it

Having established a location for our sound, we need to consider how to place it there A stereo recording allows us to locate it on a line between the speakers A surround system adds the element of front/back allowing us to locate on a flat plane but neither approach allows us to indicate the distance of our sound from the listener In landscape painting, two ideas are used to indicate distance: an object that is far away will appear bluer

in hue and paler in tone than one that is closer (as happens in nature) We can adopt a similar tactic: a sound that is far

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away will have more reverberation than one that is close by (increased blueness) and will have less high frequencies (a paler tone) Again, this is a reflection of nature: a distant sound assumes more of the acoustic qualities of its location and is muffled compared to the ‘dryness’ and

‘crispness’ of a close one

Locational provenance confirms the status

of a classical recording (see pp.20–21) and the ephemerality of much recorded rock and pop music has been attributed to

a tendency to opt for acoustics that are spectacular rather than credible In the case of Jimi Hendrix (see also pp.76–77), the placement of microphones in the studio and the sense of space and place that was communicated by powerful amplifiers and speakers making large amounts of air move in a big room was crucial to conveying the essential qualities

of the performer and his work In establishing recorded sound works as serious art endeavours, it costs us little to ensure that the sounds that we create are appropriately placed

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