opls16projects/alex-gribov-george-mitwasi-kevin-dibble

This project uses Racket to bridge together an algorithmic music composition library (Overtone), with a digital sound synthesis software (Max/MSP), and an open-source hardware platform (Arduino) to create a novel music composition tool.

##Authors Alex Gribov George Mitwasi Kevin Dibble

Overview

This project uses Racket to bridge together an open-source hardware platform (Arduino) with a digital sound synthesis software (Max/MSP) to create a novel music editing tool. Max offers the capability to create a custom audio synthesizer, which can be controlled by MIDI input and external hardware (Note: this is a separate project that our team member George is doing for a different class). What our Racket program will do is take in user commands through the Arduino, keep track of the system's state and interacti with the MAX synthesiser. The MIDI data will be supplied to the synthesiser through MIDI input where the sound is modified through using the state of the racket program.

Diagram and Detailed Description

##Concepts Demonstrated

• Message Passing is used in the state machine to allow the system to react to a persistent state value.
• Tail Recursion The main control loop uses tail recursion to allow looping without space issues.
• Object Oriented Programming is used to pass data to MAX and provide encapsulated interfaces to do so.

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##External Technology and Libraries Briefly describe the existing technology you utilized, and how you used it. Provide a link to that technology(ies). Arduino Microprocessor https://www.arduino.cc/ This was used to implement the user interactions ** MAX MSP** https://cycling74.com/products/max/ This was used to produce and edit sounds

##Favorite Scheme Expressions ####Kevin Dibble My favorite part of the project was the state machine. I've enjoy state machines ever since I learned how to build them in Computing IV, so I was hapyp to be able to write one for this project.

(define (make-state-machine)
  (let ((state 'Main))
    (lambda (transition)
      (cond ...)
      state
      );;end lambda
    );;end let
  );;end define

####George Mitwasi My favorite part was the playnote function. It took a while to make this work without any latency, and I did so by delaying the stopnot function so that MAX has time to read in the off-note data.

(define (playnote)
  (begin (set-mcar! musicdata 1) ; toggle noteplay ON
         (send)
         (sleep .0001)
         (stopnote)))

####Alex Gribov My favorite tidbit of bits was the chunk of code where I had to use the dot notation, and Kevin helped me figure out that I need to use the apply function to call it recursively. Until then, I had no idea why apply was useful!

(provide lightsOn)
(define (lightsOn lights ind . rest)
  (digital-write (list-ref lights ind) HIGH)
  (if (not (null? rest))
      (apply lightsOn (cons lights rest))
      #t
      )
  )

###Detailed description

• MIDI input from a keyboard through the MAX synth
  • We will use the Arduino to interface with the user and Racket to interface with the MAX Synthesiser. A physical user creates sound from a physical keyboard connected via MIDI to MAX where the sound is modified baised on the interactions with the Arduino.

Under development features:

• The state machine allows for additional phases including a pichbend state and a loop set state. These features were not able to be fully implemented however due to time constraints.

#How to Download and Run Download the project zip.

Open main.rkt, click run and type (main-loop) into the REPL. Now we're running the main loop for the Aruino and all functionality with sound design should work. If you have MIDI keyboard plugged in, you can play it while editing sounds on the Arduino board.