e-RRATUM

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e-RRATUM

Duration:	10’ 13’’
Instrumentation:	for tape.
Date of premiere:	Not premiered yet.

COMPOSITIONAL AIMS.

Combining sounds created by methods of synthesis and sounds from source recordings raises problems of integration due to the divergence of the morphology and nature of the two types of sonic materials.

My aim when dealing with this compositional issue, a major fact in e-RRATUM, was to take advantage of the situation instead of rejecting the idea of combining almost incompatible spectra.

To do so and as the result of several different lines of experimentation with music software, I created a large number of hybrid sonorities of intrinsic timbre quality. These unique sound world would never had existed under circumstances of isolation, in other words transforming together sounds of the same nature (either synthesis with synthesis or source recordings with source recordings).

In this compositional environment, the processes of manipulation and intuitive selection of transformations offered me solutions of:

- integration,

- convergence and

- juxtaposition for the two sonic worlds.

Also, it helped to diminish the divergences or in desired situations to magnified them, making possible the creation of unique timbral combinations.

e-RRATUM as a piece, goes beyond the simple experimentation in hybrid textures, as it is only considered the start in the process of creation.

The composition arises its sonic discourse by a constant crossbreeding from what is ‘real’ to what is ‘synthetic’ and vice-versa in terms of the nature of the sounds. This happens at two different levels within the composition. Firstly, there are large transitions of different kinds of hybrid materials. They work in several directions as a slow-motion picture, outlining the beauty of the transformation. Secondly, the existence of small scale gestures and its articulations along side the slow transitions mentioned before. As an example of the last, there are several gestures of the ‘classic’ sound of a ‘squeaking door’ which play multiple roles in the composition. For instance:

a) as a linear motif for transitions: the door ‘slam’ in combination with non pitched sounds acts as a transitional sound, leading the user to the next sonic phrase.

b) as an abstract object: several doors squeaking in parallel at different speeds and pitch whilst we expect the door to slam which never happens. It reinforce our perception of the sound as it is and away from other connotations.

c) as a sonic metaphor: the door squeaks rhythmically emerging as a solo voice from the synthesis background and vice-versa, focusing and unfocusing the two contrasted materials.

The acousmatic ‘sonic literature’ is plenty of pieces with similar examples in the use of door sounds, to mention a few, Trevor Wishart’s redbirds, Robert Normandeau’s Rumeurs and François, Bayle’s Tremblement de terre trës doux . In e-RRATUM squeaky sounds belong to a collection of the multiple small scale events that happen almost sequentially. Another important example is the sounds of Cuban hand-made trolleys of booksellers moving around in a ‘three dimensional effect’, they also work as a linear motif for transitions but there are more examples. i.e. metallic objects, non pitched sounds, coins falling on an empty and rusty tank etc. These sounds and its transformations interlock and interact with the sounds created by synthesis at different levels within the structure of the piece which is mostly intuitive.

I restricted dramatically the sounds spectra of e-RRATUM in contrast with my previous tape pieces which include a greater variety of sources.

The restriction consisted of a block of six transformation of the following sources:

Doors material: squeaking, slamming, transposed up and down, time –stretched, delayed.

Synthesis (scanned method).

Warm-reverberated synthesis sound.

Trolleys moving in a three dimensional space.

Rubber over fibre-glass surface.

Non pitched sounds.

It contributed to create a large sense of unity in terms of sound and texture all over the composition. Also, the restriction in starting materials forced my to intensify my studio work being more selective and including sounds with very little variation from the sources alongside others with a high degree of transformation.

Samples included in the auxiliary audio CD:

STRUCTURE

The structure is mostly intuitive and there are not clear sections or locks of ideas. Form one perspective I perceive e-RRATUM’s form as a linear journey of multiple combination of the six families of sound. Successions of phrases and superimposition of large layers of texture in constant evolution.

From a different perspective it could be understood as a static framework encapsulating a set of musical timbres with contrasted identities and a camera turning around them. Under this different point of view I see recursive ideas and constant reference to musical sentences exposed before which but from a different angle.

There are series of motifs with a clear function of connecting passages in the context of the piece.

This is a snapshot picture of the structure from a linear perspective:

Apart from the studio techniques explained on next chapter, we observe multiple appearances of every of the six blocks of sounds. In every occasion there is a different transformation of the source materials according to the demands of the musical discourse at this particular point.

Scanned synthesis material and its variations serve in occasions as colourful layers to support recorded material but in some other times constitute part of the spectra of a hybrid sound or it can be found as the sustain and release of a connecting passage that leads to a different musical phrase and function as a point of intersection of ideas.

The sounds of the trolleys range from the two extremes of the possible degrees of transformation of a sound.

We find passages with the original recording as in minute 10”00 (apart from the basic processes of editing and cleaning up) and others extremely transformed as in minute 3’40”.

A particularity of the trolley sounds comes from the way I recorded them. My idea was to contrast the use of artificial panning and doppler effect in studio with the real sensation of recording it. In some way the preparation of this recording experiment of a natural panning and doppler effect was influenced by studio techniques which are inspired in real situation like this.

As we see in the picture before, I placed the microphone in the middle o ‘reverberated’ squared space where hand-made trolleys with different amount of weight pulled by book sellers with metallic wheels and a few broken ball bearings were approaching and crossing the microphone from multiple directions at different speeds. The floor was an old pavement of squared stones which produced a very interesting sound which I dramatically abstracted from its significance.

It may sound contradiction but we composer often forget that most of the studio effects as reverberation, panning, echo etc are simulation of real acoustic situation implemented in a surreal way. In this cause I used both real and studio situation to move deliberately sound across the space.

Chronologically the piece starts with a ‘studio’ panning effect of a metallic sound three seconds long. It leads to the first ‘soundscape’, a hybrid mix of layers from time-stretched effect on sources to scanned synthesis experiments with added reverb. At second 28” appears the first squeaky sound functioning as a transition space from the hybrid to a comb filtered experiment of water dropping inside a resonant tank. It last for 31 seconds and it is briefly reminded very subtly at the very end of the piece.

Before the second door sound appears at second 59”, which is very similar to the one a 28” but cloned, delayed and transposed up, another long shape of more pure synthetic material fades in. Next, at minute 1’42” we have a hybrid sonic gesture with a sharp attack made of door sounds and a large release mixed of two types of scanned synthesis and for the first time, the sounds from the trolleys. They expand and evolve until minute 2’ 32” .

These trolley sounds are very visual and have an effective impact in the ear when moving in an abstract space. It is probably due to they inner structure of repetitive and mechanical loops. They have multiple associations with train-like sounds which help our perception to imagine this sound in motion and travelling when it is abstracted from its original context. At 2’57” there are a few short hybrid gestures interrupted by dramatic period of silence.

This is a very distinctive part of the piece as there are no other moments of silence thorough. After this, synthesis and trolleys-like trajectories are interlaced over a recurred warm layer similar to the one at the start of the piece.

At minute 4’16” we perceive a very similar situation than in minute 2, characterised by the presence of hybrid objects, but it naturally evolves differently. The objects scale is smaller and the weight of the sources varies. It is also reinforced by the presence of non pitched sounds in the background starting at minute 4’30”.

Sounds of smashed glass are presented over a continuos layer of trolleys circulating in different direction in the three dimensional space plus the synthesis material fading out. The sparkly nature of the glass has a similar effect of random passage of erratically accentuated brass semiquavers over a slow chord progression of sustained strings. It last for a minute whilst other small scale objects are included to enrich the texture.

Minute five (4’57”) starts a dramatic change not only in timbre but overall in gesture. This is another distinctive section better explained later on when talking about the divergence of sources and the use of MaxMSP. It is a collection of nervous gesture of rubber sliding over different fibre materials and manipulated in real-time with a very effective cross-panning movement. It also holds insertions of previous source materials which interlock in a very unpredictable way.

These sonic picture progresses until 6’47” where we find a major change to high-low textures and a synthesis motif in between. Some kind of ‘ssshhh’ onomatopoeia. At 7’20” starts the preparation of the climax, consisting of a fade in of wooden material plus synthesis solos. The climax arrives at 8’32” and last for 20 seconds until 8’52”. It is a mix of previous sounds and new spectra, condensed and accentuated erratically. It is not characterised for being loud in dynamics but it definitely concentrates the energy of the piece which dissipates during the last minute and twenty one seconds. The very last sound, a single trolley appears once the piece apparently has already ended.

TECHNICAL ASPECTS TO ACHIEVE COMPOSITIONAL TARGETS.

I applied different techniques aiming to achieve soundscapes and smaller scale situation of:

Integration

Convergence

Divergence

Morphing

1) INTEGRATION: ‘Scanned synthesis by injection’ / Csound.

By implementing scanned synthesis algorithms, (invented in 1999 by Bill Verplank, Max Mathews and Rob Shaw) in Csound with scores created in Microsoft Excel. I designed textures of synthesis with great control over some 22 parameters. The target was to design extended synthesised timbres and rhythms imitating pre-recorded sounds.

The time domain is the millisecond where insignificant variations of a parameter’s value have dramatic consequences in the final timbre and texture.

As an example, next Csound-scanned synthesis orchestra and score, generates a second of sound convoluted by the injection of an audio file called band.wav, recording from a percussion marching band.

orchestra

iamp	=	ampdb(p4)
iamp	=	iamp*.5
a0		soundin	banda.wav
a1		=		a0/30000
		scanu		p6,p7,p8,p9,p10,p11,p12,p13,p14,p15,p16,p17,p18,p19,p20,a1,p21,p22
a2		scans	iamp, cpspch(p5), 7, 0
a3		scans	iamp, cpspch(p5)*1.01, 77, 0
		outs			a3+a2+(a0.1), a3+a2+(a0.1)
		endin

score

; instr

start

dur

ampdb

cpspch

init

irate

ifnvel

ifnmass

ifnstiff

ifncentr

ifndamp

kmass

kstif

kcentr

kdamp

ileft

iright

idisp

;p1

p10

p11

p12

p13

p14

p15

p16

p17

p18

p19

p20

p21

p22

400

1,00

0,01

2.1

0,1

0,12

-0,01

0,16

0,5

0,998