Root Key

Outputs the root note of Bitwig's current global key signature as a Grid pitch signal.

What it does #

The current editorial summary is: Outputs the root note of Bitwig's current global key signature as a Grid pitch signal.

Root Key follows the project-wide key signature and turns its tonic into a usable pitch value. Octave chooses the register, while Wrap Key decides where higher pitch classes should be placed one octave lower to keep the output in a preferred range.

Controls and ports #

Control	Label	Official description
out	Out	Root key formatted as pitch
octave	Octave	The MIDI octave that outgoing messages start with
wrap_key	Wrap Key	The key where outgoing messages will drop down an octave. The setting is available for all Octaves except '-2'. For example, 'G♯ / A♭' would place root keys from C to G within the set Octave, and G♯/A♭ up to B would land one octave below. And if set to 'C', all notes will be sent in the original Octave.

Practical uses #

• Drive oscillators or pitch processors from the tonic of the current global key signature.
• Subtract a fixed Pitch Class from Root Key to calculate the transposition needed when the project changes key.
• Use it as the reference pitch for scale-aware chord, bass, or drone patches.

Things to know #

• The output follows global key-signature changes; it is not derived from the most recently played note.
• Wrap Key changes octave placement without changing the pitch class.
• A global key change can alter a sustained result immediately, so use Sample/Hold when the value should remain fixed for the lifetime of a note.

Technical details #

A high-confidence Nitro implementation candidate supports the technical summary, but the visible-module mapping remains inferred.

The mapped Nitro module reads the global key-signature root and calculates key = root_class + 12 * (octave + 2). When Wrap Key is enabled and the root class is at or above that threshold, it subtracts 12 semitones, except in octave -2. The key is then converted from semitones into Bitwig's pitch-signal domain; a parallel internal output retains the semitone number.

Nitro port	Type
ksig_hash	InputValuePortType
octave	InputValuePortType
wrapping_pitch	InputValuePortType
out	OutputAudioPortType
pitch_out	OutputAudioPortType

Simple process assignments:

• out = fromSemitones(cast(key, f32))
• pitch_out = cast(key, f32)

Open questions #

• None currently.

Version and sources #

Checked against Bitwig Studio 6.0.6. This page combines Bitwig's module metadata, the existing Grid course and guides, and Nitro analysis where the mapping is strong enough to support a technical statement.

Related material #

• Bitwig 6 Preset for Global Scale and Root Note Transposition
• Bitwig Studio 6 Scale Highlighting Feature Explained

Return to Bitwig Grid Modules or the Grid Modules course lesson.