Chiptune

Chiptunes
Stylistic origins	Video game music
Typical instruments	Sound chips, trackers, synthesizers

In the early 1980s home computers became cheaper and more accessible than they had previously been. This lead to a proliferation of personal computers and gaming consoles that were abandoned as users moved on to the next generation of software, and the hardware to run it. Despite this, small groups of artists and musicians continue to use these forgotten computers to produce audio and visual work. While both together tie into the demoscene, the music alone is commonly known as chiptune (or chip music). The game technologies that are typically used in chip music production are those produced from the 1980s up until the early to mid 1990s. These systems, including the Commodore 64, Nintendo Game Boy and Nintendo Entertainment System were aimed at the domestic consumer market. These systems were unique in that they marked a period in the technological development of game audio in which dedicated hardware sub-systems or sound chips were used to create sound. It was after this period that video game audio progressed onwards to sample playback and wavetable synthesis techniques, replacing the dedicated sound chip-based techniques that had been used previously to synthesise sounds in real time. Sample playback uses computer memory to store a pre-recorded sound, which may be played back at a fixed or variable pitch, and can be repeated in a continuous loop to extend the duration of a sound without increasing the memory requirements. Low quality sample playback as used in various Amiga machines, and tracking software such as Renoise is still often accepted within chip music communities, depending on the sonic properties and hardware used in composition. In fact it is arguable that the term ‘chip music’ was originally used in reference to the sample based tracker style of music on the Amiga and similar platforms, however, in its modern form, the terms ‘chip music’, and ‘chiptune’ refer to music made by the sound chips found within early gaming systems and microcomputers.

A waveform generator is a fundamental module in a sound synthesis system. A waveform generator usually produces a basic geometrical waveform with a fixed or variable timbre and variable pitch. Common waveform generator configurations usually included two or three simple waveforms and often a single pseudo-random-noise generator (PRNG). Available waveforms often included pulse wave, the timbre of which can be varied by modifying the duty-cycle, triangle wave, which has a fixed timbre containing only odd harmonics, and saw-tooth wave, which has a bright raspy timbre and contains odd and even harmonics. Two notable examples of systems employing this technology include the Game Boy, with two pulse channels (switchable between 12.5%, 25%, 50% and 75% wave duty cycle), a channel for 4-bit PCM playback, and a pseudo-random-noise generator. The Commodore 64 on the other hand made use of the MOS Technology SID chip which offered 3 channels, each switchable between pulse, saw-tooth, triangle and noise. Unlike the Game Boy, the pulse channels on the Commodore 64 allowed full control over wave duty cycles. The SID was technically a very advanced chip, offering many other features including ring modulation and adjustable resonance filters.

Due to the wide range of video game systems available, with different sound chips and processors running them, each system, while sharing the same basic synthesis techniques, had a fairly unique sound. Even within a specific system, sound qualities often varied between batches of sound chips, as happened with the many SID revisions used throughout the production of the Commodore 64.

The term Chip Music has been applied to more recent compositions that attempt to recreate the chiptune sound, albeit with more complex technology. Currently, chip music composers use modern computers to aid them in either composition, recording, or execution of the art form. Modern computers are also used for networking throughout the global chip music "scene." The evolution of the Internet has helped chip musicians connect with each other, share ideas, and create public events. The recent popularity of Creative Commons over Copyright in the chip music scene has also helped many musicians learn and develop their craft through an open source environment. Emulation of the original sound chips has become more prevalent and accepted because of the increasing rarity and fragility of the original video game systems and microcomputers used.

History

Origins

The earliest precursors to chip music can be found in the early history of computer music. In 1951, the computers CSIRAC and Ferranti Mark 1 were used to perform real-time synthesized digital music in public.

In the late 1970s, video game consoles and microcomputers started to have integrated circuits with dedicated sound logic. A notable early example is the TIA chip of the Atari VCS (1977) featuring two voices with separate volume and waveform setting.

As several microcomputers were marketed with their music and sound capabilities, commercial music software became available for many models. An early example is the Atari Music Composer released in 1980 for the Atari 400/800. These programs were typically simple and easy to use, but very restricted in their capabilities. In order to really take advantage of the sound chips, programming skills were required.

SID music culture

MOS 6581 and 8580 Commodore 64 SID chips.

Named by PC World Magazine as one of computing's most important inventions, the Commodore 64's MOS Technology SID played a major role in chiptune development. By 1985, several Commodore 64 programmers, such as Rob Hubbard, David Whittaker and Martin Galway, were exploring the musical capabilities of the SID chip in order to produce varying and interesting video game music. In the absence of sufficiently advanced music editor software, machine code monitors were typically used for the purpose.

At the same time, several computer hobbyists were taking efforts in "ripping" this music out of the games. The ripped music was spread among hobbyists as stand-alone executables containing one or more pieces of game music, and it was also used as background music in crack intros and demos.

Later on, several demo groups moved to using their own music instead of ripped game music. In 1986, Jeroen "Red" Kimmel studied Rob Hubbard's player routine and used it for original demo songs before writing a routine of his own in 1987. Hobbyists were also writing their own dedicated music editor software, such as Chris Hülsbeck's Soundmonitor which was released as a type-in listing in a 1986 issue of the German C-64 magazine 64'er. The availability of such software made it possible for a wider range of computer users to compose advanced SID music. The 64'er magazine also hosted the earliest known competition for Commodore 64 music in 1986.

These developments in the Commodore 64 culture were reflected by similar developments on other popular microcomputer platforms of the era.

The practice of SID music composition has continued seamlessly until this day in conjunction with the Commodore 64 demoscene. The High Voltage SID Collection, a comprehensive archive of SID music, contains over 36,000 pieces of SID music.

Tracker chiptunes

Commodore Amiga (1985), with its sample-based sound synthesis, distanced the concept of microcomputer music away from plain chip-synthesized sounds. Amiga tracker music software, beginning from Karsten Obarski's Ultimate Soundtracker (1987), inspired great numbers of computer enthusiasts to create computer music. As an offshoot of the burgeoning tracker music culture, a type of tracker music reminiscent of Commodore 64 SID music was born. This type of music came to be called "chiptunes".

Earliest examples of tracker chiptunes date back to 1989–1990 and are attributed to the demoscene musicians 4-Mat, Baroque, Turtle and Duz. Tracker chiptunes are based on very short looped waveforms which are modulated by tracker effects such as arpeggio, vibrato and portamento. The small amount of sample data made tracker chiptunes far more space-efficient than most other types of tracker music, which made them appealing to size-limited demoscene demos and crack intros. Tracker chiptunes have also been commonly used in other warez scene executables such as keygens.

Nowadays, the term "chiptune" is also used to cover chip music using actual chip-based synthesis, but some sources, such as the Amiga Music Preservation project, still define a chiptune specifically as a small tracker module.

Steps toward the mainstream music world

Before the 2000s, chip music was rarely performed live, except by Coin, and the songs were nearly exclusively spread as executable programs and other computer file formats. The earliest examples of record label releases of chip music can be found in the late 1990s.

During the 2000s, a new wave of chiptune culture took place, boosted by the release of software such as LittleSoundDJ for the Game Boy. This new culture has much more emphasis on live performances and record releases than the demoscene and tracker culture, of which the new artists are often only distantly aware.

Technology

Historically, the chips used were sound chips such as:

• the MOS Technology SID on the Commodore 64
• the analog-digital hybrid Atari POKEY on the Atari 400/800 and arcade hardware
• Ricoh 2A03 on the Nintendo Entertainment System or Family Computer
• AY-3-8910, or 8912 on Amstrad CPC, Atari ST(Yamaha YM2149), Atari Falcon(Yamaha Y3439-F) MSX and Sinclair ZX Spectrum 128.
• Yamaha YM2612 on Genesis/Mega Drive
• Yamaha YM3812 on IBM PC compatibles

For the MSX several sound upgrades, such as the Konami SCC, the Yamaha YM2413 (MSX-MUSIC) and Yamaha Y8950 (MSX-AUDIO, predecessor of the OPL3) and the OPL4-based Moonsound were released as well, each having its own characteristic chiptune sound.

The Game Boy, like the NES, does not have a separate sound chip but both instead use digital logic integrated on the main CPU.

Paula is known as the sound chip on Amiga, but is not really a sound generating chip by itself. It is only responsible for DMAing samples from RAM to the audio output, similar to the function of modern day sound cards.

AY-3-8912 chip, Amstrad CPC, Atari ST, MSX and Sinclair ZX Spectrum 128

On the ZX Spectrum 128k models, Amstrad CPC, and Atari ST, chip sounds are synthesised by simply dividing a clock square wave to get a square wave of desired frequency, and then using a sawtooth/triangle wave from volume LFO or an (ADSR) envelope to get some kind of ring modulation. The actual sound generation on the Sinclair ZX Spectrum/Timex series and later badged Amstrad non-CPC version evolved from a variation of the combined oscillator system that made up the tone generation system for the tape/cassette output on the original ZX80/81 series; even in the Spectrum, this slaved oscillator was used to provide the output tones for the tape/cassette output, in contrast to the discrete sound chip based system system used by the Amstrad CPC and Atari ST and a discrete tone generation circuit used for tape/cassette output on the Amstrad CPC series.

The technique of chiptunes with samples synthesized at runtime continued to be popular even on machines with full sample playback capability; because the description of an instrument takes much less space than a raw sample, these formats created very small files, and because the parameters of synthesis could be varied over the course of a composition, they could contain deeper musical expression than a purely sample-based format. Also, even with purely sample-based formats, such as the MOD format, chip sounds created by looping very small samples still could take up much less space.

As newer computers stopped using dedicated synthesis chips and began to primarily use sample-based synthesis, more realistic timbres could be recreated, but often at the expense of file size (as with MODs) and potentially without the personality imbued by the limits of the older sound chips.

General MIDI is not considered chiptune as a MIDI file contains no information describing the synthesis of the instruments.

Common file formats used to compose and play chiptunes are the SID, SAP, YM, SNDH, MOD, XM, several Adlib based file formats and numerous exotic Amiga file formats.

Style

Generally chiptunes consist of basic waveforms, such as sine waves, square waves and sawtooth or triangle waves, and basic percussion, often generated from white noise going through an ADSR envelope or PCM samples.

For the above reasons the classic chiptune sound can be recognised from its simple instruments, white noise or low-quality samples used for percussion and heavy use of ultra-fast arpeggios to emulate chords of three or four notes on a single channel (due to hardware limits, several notes must be placed on the same channel).

Today

Modern computers can play a variety of chiptune formats through the use of emulators and platform-specific plugins for media players. Depending on the nature of hardware being emulated, 100% accuracy in software may not be available. The commonly used MOS Technology SID chip, for example, has a multi-mode filter including analog circuits whose characteristics are only mathematically estimated in emulation libraries.

The chip scene is far from dead with "compos" being held, groups releasing music disks and with the cracktro/demo scene. New tracker tools are making chip sounds available to less techy musicians. For example, Little Sound DJ for the Game Boy has an interface designed for use in a live environment and features MIDI synchronization. The NES platform has the MidiNES, a cartridge that turns the system into a full blown hardware MIDI controlled Synthesizer. Recently, for the Commodore 64, the Mssiah has been released, which is very similar to the MidiNES, but with greater parameter controls, sequencing, analog drum emulation, and limited sample playback. The Commodore PET has the open-source PetSynth software, which uses the PET's 6522 chip for sound, allows the computer to be played like a piano keyboard, and features many effects. On the DOS platform, Fast Tracker is one of the most famous chiptune makers because of the ability to create hand-drawn samples with the mouse. Chiptune artist Pixelh8 has also designed music software such as Music Tech for the Game Boy and the Pro Performer for the Game Boy Advance and Nintendo DS which turn both machines into real time synthesizers.

In the last couple of years, chip music has returned to modern gaming, either in full chip music style or using chip samples in the music. Games that do this in their soundtrack include Mega Man Battle Network, Reset Generation, Seiklus, Tetris DS, Sonic Rush, Scott Pilgrim vs. the World: The Game and VVVVVV. Furthermore, the Electronic Frontier Foundation in December 2010 used a faux 8-bit game with an 8-bit sound track by crashfaster to demonstrate its notable legal achievements for that year.

Film

The chiptune scene was recently the subject of a documentary called Reformat the Planet by 2 Player Productions[2]. This film was an official selection at the 2008 South by Southwest Film Festival in Austin, Texas. The premier took place on March 8, 2008 at the Dobie Center.

Scott Pilgrim vs. the World features a chiptune version of the song Threshhold performed by Brian LeBarton in latter part of the ending credits.

TV

There have been a number of television segments featuring chiptunes and chip music artists in the past few years. On the 11th of April 2005, the first ever broadcast of a chiptune performance took place. 8 Bit Weapon played their songs "Bombs Away" & "Gameboy Rocker" on G4's Attack of the Show live broadcast Episode #5058.

Another chipmusic feature include little-scale, Dot.AY, Ten Thousand Free Men & Their Families and Jim Cuomo on the ABC Australia television series Good Game.

Br1ght Pr1mate, a Boston-based chiptune band, performed on Fox News on the 10th of July, 2010.

There are a few shows that make use of chiptunes as background music. Two of these include the Nickelodeon TV series Yo Gabba Gabba! and Cartoon Network Adventure Time.

Chiptune music is repeatedly featured on episodes of the Engadget show, often with live performances from chiptune artists, including Bit Shifter, Glomag, Neil Voss, Nullsleep, Zen Albatross, and Kris Keyser.

See also

• Elektron SidStation - Professional synthesizer with a built-in SID chip
• HardSID - A PCI card for modern computers that features from 1 to 4 actual SID chips
• SLAY Radio - Commodore 64 Remixes
• The High Voltage SID Collection - Commodore 64 music archive
• Game Boy music

References

• Kevin, Driscoll; Diaz, Joshua (2009). "Endless loop: A brief history of chiptunes". Transformative Works and Cultures, no. 2. doi:10.3983/twc.2009.0096.

External links

• Chiptune Synthesis – modern and historical chiptune synthesis techniques
• Delek's Site – Chiptune musican
• Aural Stimulation – Chiptune musician
• Anamanaguchi - Chiptune band