Strangelight Audio
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Data Types and Conversion

Every patch connection in Throughline depends on a data type.

Most of the time that means a cable kind such as audio, control, gate, trigger, or MIDI. Some node settings also use fixed enum-style values instead of numeric ranges.

Some connections work directly. Some compatible pitch and control-domain connections are automatically interpreted on the edge. Others require an explicit conversion node.

If a connection works but feels surprising, check the node reference for that port’s Kind, Unit, Range, and Coercion.

The Main Data Types

Audio

Audio is a continuous signal stream.

In the node reference it appears as audio, usually with a normalized range of -1 to +1.

Use audio for sound generation and processing:

  • Oscillators
  • Samplers
  • Filters
  • Effects
  • Outputs

Examples: Oscillator, Gain, Mix, Audio Output

Numbers and control signals

Most numeric cables in Throughline are of type control.

control is a shared data type for numeric signals — but the unit defines the meaning.

For example:

  • gain01 → level (0 to 1)
  • Hz → frequency
  • v/oct → pitch
  • midiNote → note number
  • ms / s → time

Two cables may both be control, but behave completely differently depending on their unit.

Examples: Value, LFO, Map Range, Clamp

String enum values

Some node settings are not numeric at all. They are catalog-defined string enum values.

Typical examples:

  • Oscillator Waveform
  • Filter Filter Type
  • Filter Topology
  • ADSR Curve

In current user-facing patches, you will usually see these as parameter or mode selections rather than ordinary modulation cables.

Important constraints:

  • Allowed values come from the node catalog, not from numeric indexes
  • Numeric signals do not coerce into these values
  • You normally choose them from the node UI instead of patching them like generic control signals

Treat these values as named modes, not hidden numbers.

Gate

A gate is an on/off signal that stays high for a duration.

Use it for:

  • Note holds
  • Envelopes
  • Toggles
  • Logic

Trigger

A trigger is a short, one-shot pulse.

Use it when something should happen once at a specific moment.

A gate is a held state. A trigger is a momentary event.

Examples: the Trigger output of MIDI Decode, the Changed output of Compare, and the Reset inputs on Clock, LFO, and Shaper.

MIDI

MIDI is a structured event stream.

It carries:

  • Note on/off
  • Velocity
  • Controllers
  • Channel data

It is not just a number.

Examples: MIDI Input, MIDI Decode, CC Extractor, MIDI Encode

Visual and other specialist types

Some node families use specialist data (for example images or colours).

These types usually do not convert automatically and are mostly used within their own node families.

Signal Type Reference

Every signal kind that can flow between ports, with its normalized range and unit hint. This table is generated from the canonical signal-type vocabulary, so it always matches the editor's socket tooltips.

Kind Name Meaning Range Unit
audio Audio Full-band audio signal -1 to 1 float
control Control Normalized control/CV signal for parameter modulation 0 to 1 normalized cv
string String String-backed enum value catalog-defined string
gate Gate Gate signal (0/1) 0 or 1 gate
clock Clock Musical phase clock signal beats from clock origin beats
timeSignature Time Signature Musical meter carried as numerator and denominator positive numerator / power-of-two denominator meter
trigger Trigger Trigger pulse 0 or 1 trigger
midi MIDI MIDI note/CC data 0-127 note numbers / CC
scale Scale Musical key and scale selection catalog-defined scale
number Number Control/parameter value 0-1 (unipolar) number
event Event Discrete pulse/clock/gate 0 or 1 gate/trigger
sequence Sequence Timed step sequence with values and durations varies steps
bool Boolean Boolean/toggle true/false —
bufferAudio Buffer Audio Audio buffer n samples buffer
bufferFFT Buffer FFT FFT buffer spectrum buffer
image Image 2D raster image (RGBA) 0-255 per channel pixels
color Color RGBA color value 0-1 per component rgba
unknown Unknown Unconnected wildcard input; adopts the connected signal type varies —

Units

control signals share one data type but carry different meanings depending on their unit. These are the units you will see in the node reference.

Unit Name Meaning
Hz Hertz Frequency in cycles per second
kHz Kilohertz Frequency in thousands of cycles per second
cents Cents Pitch offset — 100 cents per semitone
semitones Semitones Pitch offset in semitone steps
octaves Octaves Pitch offset in octaves
midiNote MIDI Note MIDI note number (0–127, 69 = A4)
midiVelocity MIDI Velocity MIDI note velocity (0–127)
midiChannel MIDI Channel MIDI channel number (1–16)
midiCC MIDI CC MIDI continuous-controller value (0–127)
v/oct Volts per Octave Pitch CV — one unit per octave
bpm BPM Tempo in beats per minute
beats Beats Musical position or offset measured in quarter-note beats
ms Milliseconds Time in thousandths of a second
s Seconds Time in seconds
samples Samples Time in audio samples
dB Decibels Level in decibels
normalized Normalized Unitless value in a shared normalized range
gain01 Gain (0–1) Linear level from 0 (silent) to 1 (unity)
phase01 Phase (0–1) Normalized phase across one cycle
pan Pan Stereo position from left (−1) to right (+1)
degrees Degrees Angle in degrees
Q Q Filter resonance / quality factor
ratio Ratio Dimensionless ratio between two quantities
percent Percent Proportion expressed from 0 to 100
mix01 Mix (0–1) Dry/wet blend from 0 (dry) to 1 (wet)
bits Bits Resolution in bits
grainsPerSec Grains per Second Granular density in grains per second
count Count Integer count of discrete items
division Division Musical time division (e.g. 1/4, 1/8)

Same Type, Different Meaning

Two ports can both carry control data and still mean very different things.

  • 0.5 gain01 → half volume
  • 0.5 v/oct → pitch
  • 440 Hz → frequency
  • 69 midiNote → A4

Always match both:

  • the type (e.g. control)
  • and the unit (e.g. Hz, gain, pitch)

What Normalization Means

Normalization defines a shared expected range.

Common examples:

  • Audio → typically -1 to +1
  • Modulation → often 0 to 1 (gain01)
  • Some signals → bipolar (-1 to +1) or unipolar (0 to +1)

Normalization does not prevent clipping.

  • A normalized signal can still distort if amplified or summed.
  • Mix adds signals and does not limit the result.

Normalization is about consistency of scale, not safety.

If a signal is in the wrong range, use a remapping node.

What Coercion Means

Coercion is how Throughline handles mismatched connections.

When you connect two ports, one of four things happens:

  • Direct → types already match
  • Implicit → Throughline safely reinterprets the signal
  • Risky → allowed, but meaning may be lost
  • Forbidden → connection is blocked

In simple terms:

  • Sometimes it works
  • Sometimes it adapts
  • Sometimes it works but poorly
  • Sometimes it refuses

Each port defines its own coercion rules.

Example of a risky connection

A gate driving a frequency input:

  • Technically valid (values are 0 or 1)
  • Musically meaningless in most cases

These connections are allowed, but rarely what you want.

Practical guidance

  • MIDI → use MIDI Decode instead of relying on implicit behaviour
  • Gate/trigger → avoid using them as raw numbers unless intentional
  • MIDI and visual types → often forbid coercion entirely
  • String enums → do not accept numeric or control signals

Compatible pitch and control-domain changes can stay as direct patch cables. Use an explicit conversion node when you want that conversion to be visible, reusable, or shared by multiple destinations.

Use Explicit Conversion When You Want a Visible Conversion Point

Use a dedicated node when the conversion is part of the design you want to see and reuse. Throughline may still derive compatible pitch or control-domain conversion directly from the connection when no explicit node is needed.

MIDI to musical signals

Use:

Pitch conversion

Use Convert to make a switch between Note, Hz, and V/Oct visible in the graph.

The input meaning follows the connected upstream source when available. Use the node dropdown to choose the target pitch domain.

Control back to MIDI

Use MIDI Encode when converting signals back into MIDI events.

Range remapping

Use:

Gate and trigger shaping

Use Compare to turn a continuous control signal into a decision. Its Gate output is a held state and its Changed output is a trigger at the crossing, so one node covers both shapes. See Math and Logic.

To reshape MIDI note length rather than a control gate, use MIDI Gate Length. See MIDI Processing.

Audio level

Use:

Do not assume a control signal already matches the correct gain range.

Common Patch Examples

Keyboard to oscillator

  1. MIDI Input → MIDI Decode
  2. Pitch → oscillator pitch
  3. Gate → envelope or VCA

MIDI Input into MIDI Decode, with pitch driving an Oscillator and gate driving a VCA into the Audio Output.

MIDI CC to parameter

  1. MIDI Input → CC Extractor
  2. (Optional) Map Range
  3. Connect to parameter

MIDI Input into a CC Extractor, mapped through Map Range into an Oscillator parameter.

Modulation to parameter range

  1. Start with LFO or envelope
  2. Map Range to target range
  3. Optional Clamp

An LFO mapped through Map Range and Clamp into a Filter cutoff.

Generate MIDI from signals

  1. Generate pitch + gate
  2. MIDI Encode
  3. Send to MIDI output

An LFO driving MIDI Encode into a MIDI Output node.

Rules of Thumb

  • Match both type and unit
  • Treat control as “number with meaning”
  • Normalization is a shared range, not a safety system
  • Use explicit conversion when a conversion should be visible or reusable
  • Respect ports that forbid coercion
  • If something feels unclear, check Kind, Unit, Range, and Coercion