Electronic Music Production Board Remy Schott Florida Institute of - - PowerPoint PPT Presentation

Overview Keyboard Amplifier Sequencer Drum Machine Synthesizer Filters Final Considerations

Electronic Music Production Board

Remy Schott

Florida Institute of Technology

December 12, 2011

Remy Schott Electronic Music Production Board

Overview Keyboard Amplifier Sequencer Drum Machine Synthesizer Filters Final Considerations

Table of contents

1

Overview

2

Keyboard

3

Amplifier

4

Sequencer

5

Drum Machine

6

Synthesizer

7

Filters

8

Final Considerations

Remy Schott Electronic Music Production Board

Overview Keyboard Amplifier Sequencer Drum Machine Synthesizer Filters Final Considerations

Features

Description In this project, a board to aid the live production of electronic music was

• created. In order to facilitate user input, the keyboard was used via serial

port. Components Amplifier Sequencer Drum Machine MIDI Synthesizer Filters

Remy Schott Electronic Music Production Board

Overview Keyboard Amplifier Sequencer Drum Machine Synthesizer Filters Final Considerations

Keyboard

Description The keyboard input is implemented via serial port from the computer in which Code Composer Studio is running to the board. A Visual Basic application is used in order to read keystrokes from the keyboard and send them via the serial port to the board. In order to read these keystrokes, UART (Universal Asynchronous Receiver/Transmitter) is

• used. Since the UART interface runs as a separate task, the keyboard

input is synchronous and, therefore, the board is capable of taking keystrokes while it is doing audio processing.

Remy Schott Electronic Music Production Board

Overview Keyboard Amplifier Sequencer Drum Machine Synthesizer Filters Final Considerations

Amplifier

Description For every output component, there is a gain which can be used to emphasize or depreciate a certain sample. This variable is currently only changable in code due to usability considerations. Method of Implementation The amplifier can be modeled as the following linear equation: F = gO (1) Where: F is final signal (Short integer) g is gain (Floating point) O is original signal (Short integer)

Remy Schott Electronic Music Production Board

Overview Keyboard Amplifier Sequencer Drum Machine Synthesizer Filters Final Considerations

Sequencer

Description A sequencer is an audio device which is capable of recording, editing, playing back music. In my implementation, it merely copies the output music data to a place in memory and loops it when its hotkey has been activated. Method of Implementation A pointer is set when the record key is pressed. If the pointer is set, then the output buffer is copied to the location in which the pointer is set to. This continues until the buffer is full or the record key is pressed again. When hotkey is pressed, the content from the aforementioned pointer is copied to the output buffer.

Remy Schott Electronic Music Production Board

Overview Keyboard Amplifier Sequencer Drum Machine Synthesizer Filters Final Considerations

Drum Machine

Description A drum machine is an audio device which can simulate the sounds of drums or other percussion instruments. In my implementation, I found 10 wav files from the Roland TR-808 (a prominant drum machine released in the early 80s which was very popular in hip hop music) and stored them in memory. Then, when a hotkey was pressed, the corresponding drum sound would be played.

Remy Schott Electronic Music Production Board

Overview Keyboard Amplifier Sequencer Drum Machine Synthesizer Filters Final Considerations

Synthesizer

Description A synthesizer is an electronic instrument capable of imitating other

• instruments. In my implementation, I created a piano synthesizer which

can play 9 notes in the key of C Major from C4 (Middle C) to D5. By pressing a toggle key, it is possible to switch the output between the following three waveforms: Sine Square Sawtooth

Remy Schott Electronic Music Production Board

Overview Keyboard Amplifier Sequencer Drum Machine Synthesizer Filters Final Considerations

Filters

Description In electronic music, filters are an extremely popular way of modifying the sound of a track. In my implementation, I included 4 lowpass filters and 3 highpass filters. Method of Implementation When a key is pressed, the filter ID and a pointer to the filter coefficients is set. If a filter ID is set, then the current audio sample is filtered with the given coefficients. Pressing another filter’s key will switch to that filter. Pressing the same filter’s key will turn off the filter.

Remy Schott Electronic Music Production Board

Overview Keyboard Amplifier Sequencer Drum Machine Synthesizer Filters Final Considerations

Final Considerations

Limitations Due to the fact that a keyboard was used for input, implementing certain features (such as sweeping filters and dynamic gains) would not be intuitive since these features are best implemented via control knobs. Due to the complexity and processing power required to perform subtractive synthesis on the fly, the drum machine was not generated, but was instead created by taking samples from a popular drum machine. Keys which were sent outside of the normal ASCII character set (1-127) were read as ’?’ and therefore could not be used.

Remy Schott Electronic Music Production Board