Terminology: a taxonomy and an ontology of the gear's vocabulary

The manufacturers describe the same ideas in different words: Dreadbox's manual says EG where Elektron's says envelope, Behringer writes HPF where Elektron writes highpass, and Elektron places trigs where everyone else talks about steps. This page organises that vocabulary two ways:

• a taxonomy says what kind of thing each concept is (a VCF is a kind of filter), arranged as a hierarchy;
• an ontology adds typed relationships between concepts (a filter has parameter cutoff, an LFO modulates it) with rules about which kinds of concept each relationship may connect.

The concept scheme is written by hand in TERMS.yaml; tools/build_terms.py checks it and counts where every label occurs in the 66 converted manuals (1930 sections, 28 makers). Only the counts are published, never the manual text. The terms are also nodes in the knowledge graph, linked to the manuals that use them.

Measure	Value
Facets (top classes)	8
Concepts	119 (11 grouping nodes, 2 with two parents)
Labels (preferred + synonyms)	162
Typed relations	48, using 9 predicates
Concepts named differently by different makers	28
Homographs (one word, two meanings)	6

Taxonomy

Each panel is a facet; indentation means is a kind of. The bar shows how many of the 66 manuals use the concept under any of its names. A concept with two parents is listed in full under the first and marked (also) under the second: MIDI clock is a MIDI message by format and a sync signal by purpose.

Hover a concept for its synonyms and notes. Grouping nodes (italic) organise the tree but are not manual terms themselves, so they are not required to occur in the text.

Three modelling choices that a flat tag list cannot express:

• Synonym vs kind vs neighbour. Emphasis is a synonym of resonance (same control, different word), so it is a label on the same concept. VCF is a kind of filter, so it is a narrower concept. Trig is close to step but not the same (an Elektron trig is an event placed on a step), so the two stay separate and are linked as close matches.
• Polyhierarchy. A concept may have two parents when it genuinely belongs in two places (LFO: an oscillator by construction, a modulation source by use).
• Facets as classes. Every concept belongs to exactly one facet, and the facet is its class in the ontology below.

Ontology

The ontology is small on purpose: 9 relation types, each with a domain and range (which classes it may connect). The checker rejects a statement like "filter carries MIDI message", because carries only runs from a port to a signal. That rule turns a modelling slip into a build failure.

Boxes are facets; arrows are kinds of relation between them, with how many statements of each kind. Loops are relations inside one class (a song contains chains, a chain contains patterns).

One worked example: the filter, the kinds of filter, its parameters, and what modulates them. It reads both ways: the taxonomy says ADSR is a kind of envelope, the ontology says an envelope modulates cutoff, so the graph can conclude that an ADSR modulates cutoff without anyone writing that down.

Each box shows the preferred label and its synonyms. Hollow arrowheads are is-a links (taxonomy); filled arrowheads are typed relations (ontology).

Relation, and the classes it may connect	Statements
has parameter synthesis block / effect / sequencing / signal → parameter	oscillator → waveform; oscillator → pulse width; oscillator → detune; filter → cutoff; filter → resonance; filter → keytrack; envelope → envelope stage; delay → delay time; delay → feedback; effect → bypass; sequencer → tempo; sequencer → swing; step → gate length; note on → velocity; MIDI clock → tempo
modulates synthesis block → parameter	LFO → cutoff; LFO → pulse width; envelope → cutoff
carries port → signal	MIDI port → MIDI message; sync port → sync; CV port → control voltage; audio port → audio signal; USB → MIDI message; USB → audio signal
generates synthesis block / performance control / sequencing → signal	oscillator → audio signal; keyboard → note on; keyboard → aftertouch; mod wheel → control change; sequencer → note on; sequencer → trigger; arpeggiator → note on
synchronizes signal → sequencing / parameter	sync → sequencer
contains stored unit / sequencing → stored unit / sequencing	project → pattern; project → kit; bank → pattern; bank → preset; song → chain; chain → pattern; pattern → step; step → trig; kit → sample
controls performance control → parameter / synthesis block	tap tempo → tempo; expression pedal → parameter
selects signal → stored unit / sequencing	program change → pattern; program change → preset
sets sequencing → parameter	parameter lock → parameter; slide → glide; accent → velocity

Same concept, different words

For each concept, which word each manufacturer's manuals use most. Only concepts where makers with a clear favourite disagree are shown; a maker whose manuals use two words equally often is marked tied and decides nothing.

Each row is one label of a concept; each column a manufacturer. Shading is that label's share of the maker's mentions of the concept; the outlined cell is the word that maker uses most.

Concept	Word used most, by maker
MIDI message	MIDI data: Arturia, E-mu Systems, Elektron, Sonicware MIDI message: Akai Professional, Behringer, Cre8audio, Donner, Dreadbox, Korg, Roland, maker not recorded tied: Electro-Harmonix
note on	note off: E-mu Systems note on: After Later Audio, Akai Professional, Arturia, Behringer, Donner, Dreadbox, Elektron, Roland, Sonicware tied: Cre8audio, Korg
control change	CC: Akai Professional, Antumbra, Arturia, Cre8audio, Dreadbox, Elektron, Roland control change: Behringer, Electro-Harmonix, Korg, Sonicware
control voltage	CV: After Later Audio, Antumbra, Arturia, Behringer, Cre8audio, DDNIPRO, Donner, Dreadbox, Elektron, Erica Synths, Intellijel, Korg, Moth Hunter Mods, Tiptop Audio control voltage: Electro-Harmonix, Mosaic tied: Synthrotek
pitch CV	V/oct: After Later Audio, Antumbra, DDNIPRO, Elektron, Mosaic pitch CV: Arturia, Korg
MIDI THRU	MIDI THRU: Arturia, Elektron, Korg, maker not recorded thru: Akai Professional, Behringer, Cre8audio, E-mu Systems, Roland
sync out	clock output: After Later Audio, Arturia, Cre8audio sync out: Donner, Korg, Roland, Sonicware tied: Behringer
sync in	clock input: After Later Audio sync in: Arturia, Behringer, Donner, Elektron, Korg, Sonicware
CV output	CV out: Behringer, Cosmotronic, Mosaic CV output: After Later Audio, Antumbra, Arturia, Cre8audio, Elektron, Korg
CV input	CV in: Behringer, Cosmotronic, Korg, maker not recorded CV input: After Later Audio, Antumbra, DDNIPRO, Erica Synths, Intellijel, Moth Hunter Mods, Synthrotek, Tiptop Audio tied: Elektron
gate output	gate out: Akai Professional gate output: After Later Audio, Arturia, Cre8audio, Elektron, Korg, Mosaic
main out	main out: Akai Professional, Behringer, Donner, Elektron main output: Antumbra, E-mu Systems
headphone	headphone: Arturia, Behringer, Donner, Dreadbox, E-mu Systems, Elektron, Intellijel, Korg, Roland, Sonicware, Yamaha phones: Akai Professional, maker not recorded
line out	line out: Behringer, Intellijel, Roland, Sonicware, Yamaha line output: After Later Audio, Antumbra, Donner
audio input	audio in: Behringer audio input: After Later Audio, Antumbra, Cosmotronic, Cre8audio, Dreadbox, Elektron, Erica Synths, Intellijel, Tiptop Audio, Yamaha line in: E-mu Systems, Sonicware
low-pass	LPF: Electro-Harmonix, Sonicware low-pass: After Later Audio, Akai Professional, Behringer, Cre8audio, Donner, Dreadbox, Tiptop Audio lowpass: E-mu Systems, Elektron tied: Roland
high-pass	HPF: Behringer, Electro-Harmonix, Sonicware high-pass: After Later Audio, Dreadbox, Roland highpass: Elektron tied: Tiptop Audio
envelope	EG: Dreadbox, Korg envelope: After Later Audio, Akai Professional, Antumbra, Arturia, Behringer, Cosmotronic, Donner, E-mu Systems, EarthQuaker Devices, Elektron, Intellijel, Moth Hunter Mods, Roland, Tiptop Audio, maker not recorded envelope generator: Sonicware tied: Cre8audio
resonance	emphasis: Korg resonance: After Later Audio, Akai Professional, Antumbra, Behringer, Cre8audio, Dreadbox, Electro-Harmonix, Elektron, Erica Synths, Intellijel, Roland, Sonicware, Tiptop Audio tied: Donner
keytrack	key track: Dreadbox keytrack: Elektron
waveform	wave: Akai Professional, Cre8audio, Donner, Dreadbox, E-mu Systems, EarthQuaker Devices, Electro-Harmonix, Intellijel, Roland, Sonicware, Synthrotek, Tiptop Audio waveform: After Later Audio, Antumbra, Behringer, Elektron, Korg, maker not recorded tied: Jake's Custom Shop
sawtooth	saw: After Later Audio, Cre8audio, Donner, Dreadbox, Korg, Roland, Tiptop Audio, maker not recorded sawtooth: Akai Professional, Behringer, E-mu Systems, Electro-Harmonix, Elektron tied: Sonicware
glide	glide: Akai Professional, Dreadbox, Mosaic, Sonicware portamento: Behringer, Elektron, Roland tied: DDNIPRO
swing	shuffle: Roland swing: After Later Audio, Akai Professional, Antumbra, Arturia, Behringer, Dreadbox, Elektron, Korg, Sonicware
gate length	gate length: After Later Audio, Donner, Dreadbox, Elektron, maker not recorded gate time: Arturia, Roland, Sonicware
arpeggiator	arp: Arturia, DDNIPRO arpeggiator: Akai Professional, Donner, Elektron, Korg, Roland, Sonicware tied: Mosaic
retrig	retrig: Elektron retrigger: Akai Professional, Cosmotronic, Sonicware
mod wheel	mod wheel: Akai Professional, Arturia, Dreadbox modulation wheel: E-mu Systems, Korg tied: Cre8audio, Elektron

Questions the terminology answers

Both are graph queries (see the knowledge graph), each checked against separate code that reads the raw files.

Question	Answer
Which concepts do different manufacturers name differently in their manuals?	28 concepts are named differently by different manufacturers envelope: 'EG' (Dreadbox, Korg); 'envelope' (After Later Audio, Akai Professional, Antumbra, Arturia, Behringer, Cosmotronic, Donner, E-mu Systems, EarthQuaker Devices, Elektron, Intellijel, Moth Hunter Mods, Roland, Tiptop Audio, maker not recorded); 'envelope = envelope generator (tie)' (Cre8audio); 'envelope generator' (Sonicware) high-pass: 'HPF' (Behringer, Electro-Harmonix, Sonicware); 'high-pass' (After Later Audio, Dreadbox, Roland); 'high-pass = highpass (tie)' (Tiptop Audio); 'highpass' (Elektron) control-change: 'CC' (Akai Professional, Antumbra, Arturia, Cre8audio, Dreadbox, Elektron, Roland); 'control change' (Behringer, Electro-Harmonix, Korg, Sonicware) waveform: 'wave' (Akai Professional, Cre8audio, Donner, Dreadbox, E-mu Systems, EarthQuaker Devices, Electro-Harmonix, Intellijel, Roland, Sonicware, Synthrotek, Tiptop Audio); 'wave = waveform (tie)' (Jake's Custom Shop); 'waveform' (After Later Audio, Antumbra, Behringer, Elektron, Korg, maker not recorded) audio-in: 'audio in' (Behringer); 'audio input' (After Later Audio, Antumbra, Cosmotronic, Cre8audio, Dreadbox, Elektron, Erica Synths, Intellijel, Tiptop Audio, Yamaha); 'line in' (E-mu Systems, Sonicware)
Which devices' manuals describe the filter cutoff and something that can modulate it, including narrower kinds of modulator?	After Later Audio Pixie: envelope Akai Rhythm Wolf: envelope Akai Timbre Wolf: envelope Behringer K2: envelope, lfo Behringer RD-9 Rhythm Designer: envelope, lfo Cre8audio Mr. PhilTer: envelope Donner Essential B1: envelope Dreadbox Typhon: adsr, envelope, lfo Electro-Harmonix ModRex: lfo Elektron Analog Four MKII: envelope, lfo Elektron Digitakt Mk1: envelope, lfo Intellijel Quadratt 1U: adsr, envelope, lfo Korg M1 (1993): envelope, lfo Roland MC-303: envelope, lfo Sonicware Liven Texture Lab: envelope, lfo Tiptop Audio Forbidden Planet filter: envelope, lfo counted through the hierarchy (narrower kinds): adsr

Homographs: one word, two meanings

Some words mean two different things across these manuals. They are counted but assigned to no concept, because a count cannot tell the senses apart. Longer labels are matched first, so gate length and gate output are counted as their own concepts and only a bare gate lands here.

Word	Senses	Mentions (in manuals)
HP	high-pass filter (the Elektron manuals' filter pages) horizontal pitch, the Eurorack panel width unit (this site's module specs)	33 in 17
gate	the gate SIGNAL (a CV that is high while a note is held) gate length/time: how long a sequencer step's note lasts	175 in 23
patch	a stored sound (a preset) a patch cable, or the act of wiring one	46 in 17
sound	Elektron: a stored set of one track's synth parameters (a preset) sound in the everyday sense	1558 in 39
pad	a playing surface you strike (drum and trigger pads) an input attenuation switch on the audio interfaces (PAD)	298 in 15
program	a stored preset, as in 'program change' to program a sequence (the verb)	493 in 17

How it is checked

tools/build_terms.py fails the build if:

• a broader link points nowhere, loops, or a concept reaches zero or two facets;
• one label belongs to two concepts (after folding case, hyphens and plurals), or a homograph is also a concept label;
• a close match duplicates a hierarchy link (SKOS keeps the two apart);
• a relation uses an undeclared predicate, or its subject or object falls outside the predicate's domain or range;
• a concept occurs in no manual (grouping nodes excepted): a term nobody uses is invented.

Each check was tested by breaking TERMS.yaml on purpose and confirming the build fails with the expected message.

Limits

• Counts are string matches, not meanings. Whole words, case-insensitive, plurals folded, longest label first. Common words (release, trigger, step) are also used in their everyday sense, so their counts are upper bounds.
• The scheme is one person's model. The concepts were chosen from the manuals by the author with an AI assistant; the checks prove it is consistent and grounded in the text, not that it is the only reasonable model.
• Coverage follows the manuals. Gear without an ingested manual (most Eurorack modules) contributes no vocabulary.

Every concept

Facet	Concept	Also called	Kind of	Close to	Tag	Manuals
signal	audio signal	-	signal	-	audio-io	17
signal	MIDI message	MIDI data	signal	-	midi	20
signal	note on	note off	MIDI message	-	midi	17
signal	control change	CC	MIDI message	-	midi	15
signal	NRPN	-	MIDI message	-	midi	3
signal	program change	-	MIDI message	-	midi	11
signal	pitch bend	-	MIDI message	-	midi	11
signal	aftertouch	-	MIDI message	-	midi	7
signal	sync	-	signal	-	sync-clock	18
signal	MIDI clock	-	MIDI message, sync	-	sync-clock	14
signal	DIN sync	-	sync	-	sync-clock	3
signal	clock	clock pulse	sync	-	sync-clock	29
signal	control voltage	CV	signal	-	cv-gate	28
signal	pitch CV	V/oct, 1V/oct	control voltage	-	cv-gate	8
signal	trigger	-	control voltage	-	cv-gate	35
port	MIDI port (grouping)	-	port	-	midi	7
port	MIDI IN	-	MIDI port	-	midi	20
port	MIDI OUT	-	MIDI port	-	midi	16
port	MIDI THRU	thru	MIDI port	-	midi	16
port	sync port (grouping)	-	port	-	sync-clock	-
port	sync out	clock out, clock output	sync port	-	sync-clock	8
port	sync in	clock in, clock input	sync port	-	sync-clock	9
port	CV port (grouping)	-	port	-	cv-gate	-
port	CV output	CV out	CV port	-	cv-gate	11
port	CV input	CV in	CV port	-	cv-gate	17
port	gate output	gate out	CV port	-	cv-gate	8
port	trig out	-	CV port	-	cv-gate	5
port	audio port (grouping)	-	port	-	audio-io	-
port	main out	main output	audio port	-	audio-io	10
port	headphone	phones, headphone output	audio port	-	audio-io	22
port	line out	line output	audio port	-	audio-io	12
port	audio input	audio in, line in, line input	audio port	-	audio-io	16
port	USB	-	port	-	usb	18
port	connector type (grouping)	-	port	-	audio-io	1
port	TRS	-	connector type	-	audio-io	14
port	TS	-	connector type	-	audio-io	21
port	XLR	-	connector type	-	audio-io	6
port	5-pin DIN	-	connector type	-	midi	8
synthesis block	oscillator	osc	synthesis block	-	sound-design	21
synthesis block	VCO	-	oscillator	-	sound-design	7
synthesis block	sub oscillator	sub osc	oscillator	-	sound-design	2
synthesis block	filter	-	synthesis block	-	sound-design	24
synthesis block	VCF	-	filter	-	sound-design	7
synthesis block	low-pass	lowpass, LPF	filter	-	sound-design	16
synthesis block	high-pass	highpass, HPF	filter	-	sound-design	10
synthesis block	band-pass	-	filter	-	sound-design	6
synthesis block	amplifier	-	synthesis block	-	sound-design	18
synthesis block	VCA	-	amplifier	-	sound-design	12
synthesis block	modulation source (grouping)	-	synthesis block	-	sound-design	8
synthesis block	envelope	EG, envelope generator	modulation source	-	sound-design	27
synthesis block	ADSR	-	envelope	-	sound-design	3
synthesis block	LFO	low frequency oscillator	modulation source, oscillator	-	sound-design	20
parameter	cutoff	-	parameter	-	sound-design	17
parameter	resonance	emphasis	parameter	-	sound-design	19
parameter	keytrack	key track	parameter	-	sound-design	2
parameter	waveform	wave	parameter	-	sound-design	31
parameter	sawtooth	saw	waveform	-	sound-design	17
parameter	square	-	waveform	-	sound-design	24
parameter	triangle	-	waveform	-	sound-design	18
parameter	sine	-	waveform	-	sound-design	15
parameter	pulse width	-	parameter	-	sound-design	5
parameter	detune	-	parameter	-	sound-design	4
parameter	envelope stage (grouping)	-	parameter	-	sound-design	-
parameter	attack	-	envelope stage	-	sound-design	16
parameter	decay	-	envelope stage	-	sound-design	20
parameter	sustain	-	envelope stage	-	sound-design	16
parameter	release	-	envelope stage	-	sound-design	24
parameter	glide	portamento	parameter	-	sound-design	8
parameter	velocity	-	parameter	-	midi	16
parameter	tempo	-	parameter	-	sync-clock	18
parameter	BPM	-	parameter	tempo	sync-clock	14
parameter	swing	shuffle	parameter	-	sequencer	13
parameter	gate length	gate time	parameter	-	sequencer	9
parameter	bypass	-	parameter	-	effects	5
parameter	true bypass	-	bypass	-	effects	1
parameter	delay time	-	parameter	-	effects	12
parameter	feedback	-	parameter	-	effects	13
effect	time-based effect (grouping)	-	effect	-	effects	1
effect	delay	-	time-based effect	-	effects	13
effect	reverb	-	time-based effect	-	effects	11
effect	modulation effect (grouping)	-	effect	-	effects	2
effect	chorus	-	modulation effect	-	effects	8
effect	tremolo	-	modulation effect	-	effects	5
effect	distortion	-	effect	-	effects	12
effect	overdrive	-	distortion	-	effects	11
effect	compressor	-	effect	-	effects	3
sequencing	sequencer	-	sequencing	-	sequencer	26
sequencing	arpeggiator	arp	sequencer	-	sequencer	9
sequencing	pattern	-	sequencing	-	sequencer	22
sequencing	step	-	sequencing	-	sequencer	34
sequencing	trig	-	sequencing	step	sequencer	17
sequencing	song	-	sequencing	-	sequencer	10
sequencing	chain	-	sequencing	-	sequencer	16
sequencing	step attribute (grouping)	-	sequencing	-	sequencer	-
sequencing	accent	-	step attribute	-	sequencer	8
sequencing	slide	-	step attribute	glide	sequencer	15
sequencing	tie	-	step attribute	-	sequencer	10
sequencing	probability	-	step attribute	trig condition	sequencer	7
sequencing	trig condition	conditional trig	step attribute	-	sequencer	2
sequencing	micro timing	-	step attribute	-	sequencer	2
sequencing	parameter lock	-	step attribute	automation	sequencer	3
sequencing	automation	-	sequencing	-	sequencer	1
sequencing	note repeat (grouping)	-	step attribute	-	sequencer	2
sequencing	ratchet	-	note repeat	retrig, roll	sequencer	2
sequencing	retrig	retrigger	note repeat	roll	sequencer	6
sequencing	roll	-	note repeat	-	sequencer	3
sequencing	flam	-	note repeat	-	sequencer	1
sequencing	mute	-	sequencing	-	sequencer	13
sequencing	fill	-	sequencing	-	sequencer	11
stored unit	project	-	stored unit	-	presets-patterns	5
stored unit	bank	-	stored unit	-	presets-patterns	16
stored unit	preset	-	stored unit	-	presets-patterns	15
stored unit	kit	-	stored unit	-	presets-patterns	12
stored unit	sample	-	stored unit	-	presets-patterns	18
performance control	keyboard	-	performance control	-	controls-overview	28
performance control	mod wheel	modulation wheel	performance control	-	controls-overview	8
performance control	expression pedal	-	performance control	-	cv-gate	5
performance control	footswitch	foot switch	performance control	-	controls-overview	9
performance control	tap tempo	-	performance control	-	sync-clock	9