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An interview with Metin Seven by Anders Carlsson, for his master thesis about the history of chip music, August 2009.

AC: Hi Metin. I’m a tracker musician researching the history of chipmusic for a master thesis. Currently I’m looking the epistemology of the word chipmusic (or chiptune). Since you were involved with SIDmon (the first synthetic Amiga tracker, right?) I wanted to ask if you have any memories of this.

Hi Anders. That’s the coolest master thesis subject I’ve heard of so far.

SIDmon was indeed the first synth audio editor for the Commodore Amiga. Its name refers to the legendary MOS Technology 6581/8580 SID (Sound Interface Device) chip, best known from the equally legendary Commodore 64 home computer, the Amiga’s predecessor in terms of Commodore flagships. The “mon” part of SIDmon refers to “monitor” and was inspired by the first music tracker I can remember: Soundmon for the Commodore 64.

SIDmon’s interface was primitively designed compared to today’s design standards, SIDmon’s graphics reflected the game-oriented 2D graphics style of those days. It was divided in four parts: a waveform editor for creating synth sounds, a sound sample editor, a pattern editor for arranging the sounds into music patterns, and a song editor where you could combine the patterns into a four-channel song.

The SIDmon song editor

AC: My hypothesis so far is that the chiptune term occurred on the Amiga, since before there was no need to distinguish between different kinds of home computer music. Was the word first used to describe the “4-mat style” Protracker modules (with mini-samples), or did it refer to synthetic music as well, or even before that?

The term chiptune originated from the fact that the Commodore Amiga didn’t have a waveform generator in its Paula sound chip. Paula was ‘only’ capable of playing 8-bits sampled sound over a maximum of four channels and had no sound synthesis capabilities. In order to create synth-like audio, you had to work with small 8-bit audio samples and process them in a way that emulated true sound synthesis such as the SID chip’s output. That’s what our SIDmon pioneered on the Amiga, so I guess we’re partly responsible for the origin of the word chiptune. Only later people started using the word to describe early computer sound chip music in a general sense.

So why would developers in the old days want to keep on creating music with minimalistic bleeping sounds, while the Amiga had just initiated a new chapter in computer audio: four-channel music with sampled sounds? This was due to the fact that music was of secondary importance to a game, so the amount of RAM available for music was very limited, and sampled sounds usually required a reasonable amount of memory. Manipulating tiny synth audio samples offered a way to create varied music with minimal RAM resources. There was a downside though: realtime manipulation of samples / realtime synth emulation required a certain amount of processor power, depending on the complexity of the realtime sound manipulation effects. As there wasn’t much processor power in those days the second part of the chiptune challenge was to optimize the music player code so playing chipmusic took as little of the processor’s time as possible.

A second advantage of computer-generated audio was the ability to create unique custom sounds without the need for a sound sampling device. The Amiga did not have a built-in analog to digital audio converter, so in order to sample sounds you had to buy and connect separate sound sampling hardware, which could be fairly expensive at the time [at least $200 during the first years of the Amiga].

There were several characteristics of chip music. First of all the sounds were very minimalistic: basic bleeps accompanied by bass sounds and tiny drum samples. Sometimes even the drums were synthesized, imitating the SID chip’s synthdrums, based on the noise type of audio waveform. The envelope of chipsounds followed the four-phase ADSR scheme: Attack, Decay, Sustain, Release.

SIDmon’s waveform editor

Music on the Amiga was audibly separated in four distinctive channels, each playing their own instrumental track: usually a drum track, a bass track, a backing instrumental track and a leading instrumental track. Because of the lack of channels, it was difficult to achieve chords, as each simultaneous note from a chord required its own channel. To solve this, an often-heard chiptune effect was the arpeggio: notes that were very rapidly played successively in stead of simultaneously, approximating a multi-tone chord.

In the Commodore days a programmer had total control over the machine’s hardware. He could completely take over the system, directly addressing the CPU and custom chips, in stead of having to indirectly address the hardware through an operating system layer that consumes processor and RAM resources. A 3.5 inch diskette was the standard storage medium for Amiga games, and even the loading procedure was usually a custom-created piece of code by the game programmer(s). Because custom-coded loaders were an ideal way of protecting your commercial game against being cracked, they could be quite hard to crack. Most custom Amiga disk loaders started from the initial boot sector of a diskette and were full of complex checks, so in order to keep the loader of a game intact, crackers introduced the boot intro: a very tiny piece of code that had to fit into a disk’s boot sector of only 1024 bytes (1 KB). Chiptunes were an ideal small audio companion for those tiny cracker intros, which served to provide information about the cracker and options to activate the often added ‘trainer’ mode, enabling the gamer to play with unlimited lives / energy and such features. A well-known Amiga boot intro featuring a very minimalistic chip tune is the HQC [High Quality Crackings] boot intro.

The HQC boot intro

The programming techniques used to create chiptunes improved over the years, and in 1990 we released our sequel to SIDmon called the Digital Mugician, which was a more powerful sound and music editor than SIDmon.

The Digital Mugician

Although you could emulate synthesis on an Amiga, the resulting output was still limited to the 8-bit, 28.8 kHz sampled audio dynamic range of the Amiga hardware. This meant that you could not reach the pure, high-fidelity dynamic range of the Commodore 64 SID chip’s hardware-generated synthesis. This changed when several years later the first 16-bit computer audio hardware was introduced. The third and last release in our chiptune audio editor trilogy was Syntrax, a 16-bit Microsoft Windows sequel to the Digital Mugician. A simplified version of Syntrax for Windows Mobile and Symbian smartphones is available for free at Finished.nl.

Old Syntrax logo and intro picture by Sevensheaven

As the years went by and Commodore sadly disappeared from the computer scene, chiptunes turned more and more into a form of digital nostalgia, just like their visual equivalent: pixel graphics. This nostalgia resulted in a revival of the typical minimalistic chiptune sound in modern popular music, such as the electropop of Digitalism.

Download MP3s of authentic old school chiptunes by members from our former development triumvirate Team Hoi, created using the Digital Mugician and Syntrax:

Trippinsane [Mugician] by Reinier
Trippinsane [Syntrax remake] by Reinier
Waterballet [Mugician] by Reinier
Waterballet [Syntrax remake] by Reinier
Hoi game title music [Mugician] by Ramon
Hoi game level 1 [Mugician] by Ramon
Hoi game level 2 [Mugician] by Ramon
Hoi game level 3 [Mugician] by Ramon
Hoi game level 4 [Mugician] by Ramon
Hoi game level 5 [Mugician] by Ramon

A collection of original Digital Mugician modules, which can be played using DeliPlayer.

P.S.: For more digital nostalgia also check out this Amiga Future magazine interview and the Hoi Saga.