If we listen to a piece of music, it unfolds as a time-laden event.  If we consider that same piece as a spectrum, we can intuitively interact with it as a single form abstracted from linear chronology.

 Here is a spectrum taken from a recording of Mahler’s second symphony (“Urlicht”).  

The spectrum is an analytical artifact.  It reveals patterns, relationships, form.  I could zoom in and show details down to the fraction of a second - digital technology allows us to interrogate sound outside of time limited only by patience and a bit of discretionary cash.

Now.  Imagine if Mahler had begun with that image, and set about composing a piece to reveal the same form.  The compositional logic would be determined by the  visual form - not by the harmonic language, the melodic/psychologic  variations of late Vienna:  the piece composed so that a performance would have this and only this entirely specific spectral form.

Let’s consider three different species of spectral composition. 

sonic
An evolution of impressionism, a meticulous crafting of harmonics to create a specific timbre.  May mirror an existing instrument, or create an elaborate and complex evolution of sound.  Although most of the music I think of as spectral is composed using electronic means, dive in to  the composer  Giacinto Scelsi who has used orchestral resources to create music that is governed by spectral considerations. 

gestural  
Here, the spectrum is a  visual representation of form meaningful in terms of  structure or  architecture.  To help think through these ideas, I set myself the task of writing a series of pieces where the spectral building blocks are a series of rectangles.  Various sizes, some filled, some outlined with lines of different thickness.  Placed higher or lower on the frequency spectrum, overlapping or intersecting.  Overall relationships can be determined by mathematical formula.  Not being particularly adept with numbers, I choose  series like Fibonacci applied to duration (length) and frequency (height).  I worked with pure sine waves or blocks of static, and think in terms of weaving warp and woof across the spectrum.  

It is the idea that structure is a musically dominant element.  Xenakis the composer studied with Corbusier the architect.  Two interesting anecdotes:  first, Corbusier influenced the development of Pittsburgh (here, from an old Post Gazette article)

"French architect Le Corbusier, a Modernist, provided the archetype for countless urban renewal projects with his "Radiant City" concept -- a set of tall apartment and office towers surrounded by parks and superhighways.

"The whole city is a park," the architect once said."

Second:  as I sat here to write this blog, I couldn't for the life of me remember Corbusier.  I kept Googling 'Courvoisier' and wondering what the hell I was thinking.

Metanoic
This is another of my bastardized coinages.   Noia is greek for mind, and Meta is greek for ‘on steroids’.  Metanoia is a laser beam that cuts through the cerebral cortex.  Noia also appears  as the ‘noo’ in Noosphere.  

Metanoic Spectral Composition, asides from being a term that rolls over  your lips like ice cream and unfiltered Camels,  is an approach to the spectrum where the source of the visual material is more important than  the sonic output.     Ask the question:  what would the shape of Pittsburgh’s 16th street bridge sound like?  What would a spectrum taken from Sylvia Plath’s handwriting sound like,with  the spectrum of her voice reading the same text?  The  possibility for conceptual   counterpoint is considerable. 

It all requires a willingness to manipulate the technology towards a definitie if not predetermined aesthetic that  makes sure you don’t end up with crap because of too doctrinaire a commitment to the idea of it all.  

When it works, it is galactic.  Aphex Twin made an awesome track using a picture of his face.

I took an MRI of my head - the MRI where they first identified my NF2, you can see the right acoustic neuroma.  Analyzed, considered, composed with it until it became this piece, as yet untitled, but working with something  like “Galactic Mindfuck”.  It's long, over 20 minutes and is a bit unrelenting.  But I like it.

This is deeply personal, this metanoic spectral composition, it is. The composer might be is a technologist, might may be a shaman, eschataologival (outside of time, towards the end of time), fetishizing the sonic artifact.  It is a deeply romantic approach to composition.  Revealing the connections of memory.  The apperceptions of memory, the aura around a human that is the form of life (the spectral analysis of a life).