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CHIPTUNE MUSIC

Adam Sporka

05/11/18, Charles University

�@adam_sporka

DCGI, CTU Prague ⦿ Warhorse Studios ⦿ welove.audio

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My Hats

welove.audio

CTO

Middleware for adaptive music for game developers

Warhorse Studios

Adaptive Music Designer

Author of part of the music in Kingdom Come: Deliverance

Czech Technical University

Department of Computer Graphics and Interaction

Associate Professor

Research in audio-based human–computer interaction

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Outline

Intro

History and paradigms

Let’s tinker:

  • VCV Rack
  • PICO-8
  • Bassoon Tracker
  • https://beepbox.co

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Chiptune Music

Late 1970s, 1980s hardware

Real-time synthesis rather than playback

Proprietary music playback routines

Memory-efficient music formats

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Limitations

Slow computers

Little RAM

Fairly cheap hardware circuits

(Later: Fairly low CPU footprint)

  • Limited amount of channels
  • Limited amount of available timbres
  • Low temporal resolution�⇒ discrete tempo, rigid(ish) beat
  • Imprecise tuning

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Features

Strong melodies

Arpeggios rather than harmonic pads

Shared channels

Limited amount of music material

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HISTORY AND PARADIGMS

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ATARI 2600

Atari VCS (Video Computer System)

1977

2 channels

Very incomplete scales :-)

http://www.masswerk.at/rc2018/04/studio2600/

http://www.randomterrain.com/atari-2600-memories-music-and-sound.html

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ATARI 2600

CTRIX Live at Blip Fest 2011

https://youtu.be/S8e7g8kJIlo?t=1m9s

Controlled by MIDI

https://www.youtube.com/watch?v=zgDyOSDUAx0

Hands-on tip

Atari 2600 Music Kit 2.0

http://www.qotile.net/files/2600_music_guide.txt

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viznut’s Synthesizer

Hands-on tip

Playback of pseudo-chaotic sequences as PCM signal

http://www.bemmu.com/music/index.html

Sounds kinda similar, right?

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ATARI 800XL...

… and some other Atari 8-bit machines

POKEY chip

  • Keyboard handler
  • ADC sampler
  • Audio synthesizer
    • 4 Channels
    • Simple waveform generators
    • 4-bit PCM

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ATARI 800XL

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ATARI 800XL

Square wave generator controlled by clock

Frequency divider

Main clock base 64 KHz or 15 KHz

Output frequency = Clock / “Frequency”

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ATARI 800XL

Noise generator

Several modes of operation

Some usable as bass sounds

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ATARI 800XL

Pitch tuning

  • Frequency divider
  • High notes could not be tuned well

Volume control

  • Silence + 15 discreet volume levels
  • Audible jumps between the levels – unable to fade-out

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ATARI 800XL

Hands-on tip

Raster Music Tracker

by Radek Sterba

http://raster.infos.cz/atari/rmt/rmt.htm

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Commodore 64

~1982

SID = Sound Interface Device

Subtractive synthesizer

3 channels

Multiple waveforms

Frequency filters

From Commodore SID 6581 Datasheet

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Commodore 64

ADSR envelopes!

From Commodore SID 6581 Datasheet

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Commodore 64

Chipophone by Linus Åkesson

https://www.youtube.com/watch?v=m1pchpDD5EU

https://www.youtube.com/watch?v=j85kRucY8UI

Hands-on tip

SIDizer VST plugin

http://www.hypersynth.com/sidizer.html

Claims to accurately emulate the original hardware

(Including the SID bug)

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Commodore 64

Hands-on tip

Emulator + collection of some games + some demos

https://www.c64forever.com/

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Nintendo Entertainment System

Probably the most known subgenre of chiptunes out there.

“Sounds like Mario.”

Fairly simple design.

Voices with fixed wave forms:

  • Pulse wave 1
  • Pulse wave 2
  • Triangle
  • Noise
  • PCM audio

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Amiga 500

Music tracker

  • Collection of PCM samples
  • Pitch ⇔ playback rate manipulation
  • Matrix of note activations
    • Rows = points in time
    • Columns = channels
    • Cells = note X + sample Y (+ effect Zx)
  • PCM-based synthesis sometimes not considered to be an element of the chiptune culture

Hands-on tip

MOD tracker simulated in browser:

http://www.stef.be/bassoontracker/

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IBM PC: PC Speaker

“PC Master Race” wasn’t a thing back then:

Single on-board square wave generator.

Prehistoric

https://www.youtube.com/watch?v=DbjZ6qY1YPU

Star Goose

https://www.youtube.com/watch?v=JjzzSqCxwG8

Stunts (arpeggios)

https://www.youtube.com/watch?v=JQ3Qg3ora2I

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IBM PC: Creative Labs’ SoundBlaster

Combination:

  • PCM audio (sound effects)
  • FM synthesis (music)
    • Yamaha OPL2

Prehistoric via (emulated) SoundBlaster:

https://www.youtube.com/watch?v=zEDlcsGd5Lo

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IBM PC, Renaissance of Module Music

Demoscene continues.

Jazz Jackrabbit (1994)

https://www.youtube.com/watch?v=d_5EOY8QaVQ

  • FastTracker ][
  • Impulse Tracker
  • ...

Hands-on tip

Explore the structure of multichannel modules:

https://mod.haxor.fi/Falcon/sofa_surfin.xm

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Contemporary Chiptune Music

Sounds like chiptune

Using some elements of chiptune

Often not …

… produced on authentic hardware

… produced using a “traditional” form

… played back on authentic hardware

… limited by the original HW constraints

Chiptune purism

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Musicians

Rob Hubbard (Commando, Warhawk, …)

Nicholas Scharim (Spy vs. Spy)

https://www.youtube.com/watch?v=RBJn3SHfDyY

Kemal Ezcan (Cavehunt, …)

http://asma.atari.org/asmadb/search.php?play=179

Jason Brooke (Feud)

YMCK

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TINKERING TIME!

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Bassoon Tracker

http://www.stef.be/bassoontracker

An easy way to try the module music production

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PICO-8

https://www.lexaloffle.com/pico-8.php

“Fantasy console.”

Contains a fun simple tracker

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VCV Rack

https://vcvrack.com/

Get a feel for the signal path!

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Your song is in the URL!

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CHIPTUNE MUSIC

Adam Sporka

05/11/18, Charles University

�@adam_sporka

DCGI, CTU Prague ⦿ Warhorse Studios ⦿ welove.audio