The Guitar and Processing Part: 1

Due to its necessity for amplification the sound of the electric guitar is shaped and processed from the outset. Beyond the coloration provided by the amp itself, effects pedals or “stomp boxes” offer numerous ways to transform the signal or create artificial spaces and ambiences. With the advent of the home computing revolution and the democratisation of technology a new wave of sonic possibilities became available to guitarists.

Working with pedals offers a spontaneous, improvisatory approach music creation processing the guitar signal in real-time either via the use of effects pedals. Norwegian guitarist Stian Westerhus uses a wide range of pedals, particular distortion and delay units to create darkly beautiful sonic vistas. Here signal chain becomes vitally important as each pedal can colour another depending on it’s position in sequence. Along with the amp they become as much an instrument as the guitar itself.

Within this digital domain a number of artists make use of the textural possibilities of the electric guitar, sampling raw sounds of the instrument before applying a number of audio manipulation techniques such as granulation or spectral processing. Many of these processes are non-realtime requiring a different compositional workflow. Software environment Max MSP has frequently been a tool of choice, allowing composers to tailor-build audio processing tools unique to their individual needs and stylistic tastes. Christopher Willits uses a combination of Ableton and custom Max patches to build rhythmically shifting patterns from sampled chords and single note lines, a process he describes as “Folding”.

Contrastingly, Touch recording artist Christian Fennesz largely eschews rhythmic elements, utilising Max to create shifting ambient noise-scales constructed from electric and acoustic guitars, often augmenting them with field recordings. He frequently uses Lloopp, a free, pre-written suite of Max patches for sound transformation created with live improvisation in mind.

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Max 7 Harmonizer Patch

This patch came about through adopting a more bespoke approach to audio processing in an effort to further develop an individual instrumental and compositional voice. Coded in Max 7, the patch uses the gizmo~ object inside an FFT sub-patch to analyse peaks within given FFT bins before moving them along the frequency axis, shifting the sound up or down in pitch. Max 7 makes pitch shifting even easier with the inclusion of separate specific pitch shift objects without the need for a pfft~ shell however I still prefer to use pfft~ sub patches as they allow individual control over the FFT bin resolution.

GTR Harmonizer Patch wBorder

The patch also includes volume envelope control based amplitude threshold detection of the incoming audio signal and four individual delay lines (not shown in the patcher pic) routed to the two stereo output channels in pairs. In addition this post also marks a move towards recording video to document specific elements of the EP project.

Max 7: Right on Time

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For the past week I’ve had time to do a little bit of tinkering with Max 7, the newest version of Cycling 74’s powerful programming environment. Originally written as a tool for composing interactive audio, recent updates have expanded the creative possibilities available through Max, particularly in 3D graphics and animation. At a recent presentation at Huddersfield University software developer David Zicarelli commented that the majority of Max’s current user base was in fact visual artists. Despite this fact there have been a few key developments in the audio department. One of the most significant for me is the inclusion of a new time-stretch engine and dedicated pitch shifting functionality.

I recorded this brief electric guitar improvisation by routing the guitar to four separate patches, each containing pitch-shift processing object and a signal delay (there is also one non-shifted delay and dry guitar signal in the mix). I have built similar patches using older versions of the Max software, however they were slightly more complicated affairs requiring fourier transform sub-patches. Whilst it is quite clear Cycling 74 are attempting to increase their user base with Max 7, it’s nice to see composers/sound designers haven’t been left behind. On a personal level I also feel these new additions will certainly increase my efficiency and creativity within the software.