Node Reference
Analysis Nodes
Nodes that extract musical features from audio -- harmony, tension, and visualization.
Analysis Nodes
Analysis nodes extract musical features from audio and present them as signals or visual data for the editor.
Harmony Analysis
| Field | Value |
|---|---|
| Type ID | harmony_analysis |
| Category | Analysis |
| Description | Outputs 12-channel chroma distribution from pre-computed chord analysis. |
Inputs
| Port | Type | Required |
|---|---|---|
audio_in | Audio | Yes |
grid_in | BeatGrid | No |
Outputs
| Port | Type |
|---|---|
signal | Signal (N=1, T=SIMULATION_RATE x duration, C=12) |
Parameters
None.
Behavior
- Uses pre-computed consonance-ACE chord sections from the database.
- If binary logits are available, applies softmax per frame for smooth probability distributions.
- Each of the 12 channels represents a pitch class: C, C#, D, D#, E, F, F#, G, G#, A, A#, B (channels 0-11).
- Output values represent the relative strength of each pitch class at each time step.
Harmonic Tension
| Field | Value |
|---|---|
| Type ID | harmonic_tension |
| Category | Analysis |
| Description | Computes musical tension/dissonance from chroma distribution using Shannon entropy. |
Inputs
| Port | Type | Required |
|---|---|---|
chroma | Signal (C=12) | Yes |
Outputs
| Port | Type |
|---|---|
tension | Signal (N=1, T=input.T, C=1) |
Parameters
None.
Behavior
- Entropy is normalized by ln(12) to produce a 0.0-1.0 range.
- Output 0.0 means perfectly consonant (single strong pitch dominates).
- Output 1.0 means maximum dissonance (all pitches equally present).
- Useful for driving intensity or color saturation from harmonic complexity.
Mel Spectrogram Viewer
| Field | Value |
|---|---|
| Type ID | mel_spec_viewer |
| Category | Analysis / Visualization |
| Description | Computes mel spectrogram for visualization in the pattern editor. Does not produce wired output. |
Inputs
| Port | Type | Required |
|---|---|---|
in | Audio | Yes |
grid | BeatGrid | No |
Outputs
None (stored in state.mel_specs for frontend display).
Parameters
None.
Behavior
- Resolution: 128x128.
- Beat grid overlay is included in the visualization if the grid input is connected.
- This is a visualization-only node; it does not produce output signals for other nodes to consume.
View Signal
| Field | Value |
|---|---|
| Type ID | view_signal |
| Category | Analysis / Visualization |
| Description | Debug node that captures a signal for visualization in the editor. |
Inputs
First connected input (any Signal).
Outputs
None (stored in state.view_results).
Parameters
None.
Behavior
- Only active when
compute_visualizationsis enabled in the evaluation context. - Accepts any Signal type on its first connected input.
- Useful for debugging intermediate values in a graph.