The Rauschenberg Project

A performance instrument prototype for the iPad

made on Max/MSP, MIRA, and Ableton Live


This project is on hold at the moment. It will more likely be deprecated as I've found it to be somewhat overly complicated, and perhaps gratuitously so. Still, a lot of work went into the development of this instrument, so I'm sticking with the philosophy behind the design and will look forward to revisiting it in the intermediate future, hopefully with an upgraded sketch that is much simpler (and simpler to manage!).

The main idea behind this project came out of the desire to:

  • Be able to change multiple aspects of a sound with a simple gesture.
  • Play a variety of sounds and chords live, through a simple interface.
  • Be able to easily play sequences of non-contiguous timbres (e.g. one ‘key’ could play a ‘piano’ on a very low pitch, and the next ‘key’ could play the sound of a ‘bell’ on a really high pitch).
That is to say, to exploit music technology’s inherent virtues. To explain this by a contrasting example: an acoustic violin, as versatile as it is, its design limits the use of the left hand to follow the strings in the way they have been mechanically set up: one couldn’t easily detune them in realtime, or smoothly jump from one extreme of the fingerboard to the other – or for that matter, to match the fingerboard's length to a doublebass' fingerboard (the wood itself would have to be cut differently if it were indeed possible to do so!). But a computer program that is designed to playback any audio waveform whatsoever can easily switch from playing a double-bass to playing a flute sample, or flick the frequency of an oscillator quite drastically.

The Rauschenberg instrument is made up of four fader-keys. Let’s first look at the anatomy of each one: as soon as the finger touches the iPad, a sound is triggered; one can then slide the finger vertically and/or horizontally...

Here's a rough video demo of the instrument itself:

There are four layers, each with four fader-keys, which are each able to play one of four different timbres. Each fader-key is discretely connected to a group track (FK1 - FK4) and each group track is split in two: A & B...

A single track is made up of four instruments:

  • A 5-waveform analog synthesizer
  • A frequency-modulated (FM) synthesizer
  • A traditional sampler
  • A sampler with a movable-loop (for textures)

Let’s now have a look at the MIRA interface. Here’s the control surface...

...divided into the following sections:

  • The Sound Palette, a set of 15 faders per pad, divided into 3 layers (60 faders total):
    Layer 1: the first 4 faders control the timbre, the 5th fader is a global effect send (delay).
    Layer 2: the first 4 faders may be mapped to any parameters (e.g. to change the waveforms, other effects, etc.), the 5th fader being another global effect send (reverb).
    Layer 3: the first 4 faders control the amplitude envelope (Attack, Decay, Sustain, Release); the 5th fader controls the overall volume.
  • The Color Chooser allows you to switch between 4 timbres, for each Sound A and Sound B (for each pad).
  • The Preset Section is divided into two banks:
  • Chords: stores respective notes for each pad.
    Sounds: stores fader settings from the Sound Palette.
    There are 6 available presets per bank (the left and right arrows below each bank allows you to access more presets). Each preset bank is independent of the other.
  • The Interpolator is a special fader that will interpolate between preset values for all 60 fader states set in the Sound Palette. One can choose to interpolate from any two chosen presets.
  • The Pad Section is made up of the four fader-keys, plus a Sustain Pedal switch.

Below is the Chord Maker section, where one can assign a set of pitches for each pad...