MIDI Glossary

This glossary provides definitions for MIDI concepts, message types, and Kilowhat-specific terminology used throughout the documentation.

MIDI Message Types

Aftertouch

Pressure-sensitive MIDI messages sent after a note is initially played. There are two types:

Channel Aftertouch (Channel Pressure): A single pressure value applied to all notes on a channel
Polyphonic Aftertouch (Key Pressure): Independent pressure values for each note

Aftertouch enables expressive control over parameters like vibrato, filter cutoff, or volume based on how hard you press the keys after the initial note-on.

CC (Control Change)

Control Change messages are the most common MIDI message type for continuous controllers. Each CC message contains:

Channel: 1-16
Controller number: 0-127
Value: 0-127

CCs are used for faders, knobs, buttons, and most real-time parameter control. Some CC numbers have standardized meanings (e.g., CC1 = Modulation, CC7 = Volume, CC10 = Pan), while others are freely assignable.

NOTE (Note On/Off)

Note messages communicate musical pitch information:

Note On: Indicates a note has been pressed, includes velocity (0-127)
Note Off: Indicates a note has been released, may include release velocity

Each note message contains:

Channel: 1-16
Note number: 0-127 (where 60 = Middle C)
Velocity: 0-127 (0 velocity Note On is treated as Note Off)

In controller applications, notes are often used for buttons, pads, and triggers where the velocity indicates press intensity.

NRPN (Non-Registered Parameter Number)

NRPN provides 14-bit high-resolution parameter control (0-16383 range) for manufacturer-specific or custom parameters. NRPN messages are sent as a sequence of CC messages:

CC 99: NRPN MSB (parameter number high byte)
CC 98: NRPN LSB (parameter number low byte)
CC 6: Data Entry MSB (value high byte)
CC 38: Data Entry LSB (value low byte)

NRPNs are ideal for parameters requiring fine control, such as filter cutoff, pitch fine-tuning, or any parameter where 128 steps is insufficient.

RPN (Registered Parameter Number)

RPN is similar to NRPN but uses standardized parameter numbers defined by the MIDI specification. Common RPNs include:

RPN	Parameter
0	Pitch Bend Sensitivity
1	Fine Tuning
2	Coarse Tuning
3	Tuning Program Select
4	Tuning Bank Select

RPN messages use the same CC sequence as NRPN but with CC 101 (RPN MSB) and CC 100 (RPN LSB) instead of CC 99 and CC 98.

PB (Pitch Bend)

Pitch Bend messages control pitch deviation from the current note. Unlike CC messages, Pitch Bend has 14-bit resolution natively, providing 16,384 steps of control.

Center value: 8192 (no pitch change)
Minimum: 0 (maximum downward bend)
Maximum: 16383 (maximum upward bend)

The actual pitch range is determined by the receiving instrument’s Pitch Bend Sensitivity setting (typically +/- 2 semitones by default).

PC (Program Change)

Program Change messages select patches, presets, or programs on a MIDI device:

Channel: 1-16
Program number: 0-127

Kilowhat supports several Program Change modes:

Mode	Description
PC #	Send a specific program number
PC+	Increment and send the current program number
PC-	Decrement and send the current program number

Kilowhat Terms

Auto-Select Card

A Kilowhat preference that automatically selects and scrolls to a component’s card when you interact with the corresponding physical control on your controller. Enable this in Kilowhat Options for faster navigation.

Bank

A bank is a layer of MIDI messages stored in your controller. Each bank can have completely different MIDI assignments, channels, and feedback colors for every component.

Example configuration:

Bank 1: DAW mixer control
Bank 2: Synthesizer parameters
Bank 3: Effects control

Banks allow a single physical control to serve multiple purposes. Switch between banks using a designated button or encoder switch configured as a bank shifter. See Banks Overview for complete details.

Bank Shifter

A button or encoder switch configured to change the active bank on your controller. Bank shifters can operate in two modes:

Mode	Behavior
Momentary	Temporarily activates another bank while held
Toggle	Switches to another bank until pressed again

Card

The visual representation of a controller component in Kilowhat’s interface. Each card displays key information at a glance:

Hardware ID
Message type and parameter
MIDI channel and port
Feedback color/mode
User comment

Select a card to access its full configuration options. See Understanding Cards for details.

Comment

A user-defined label for a component, displayed on its card. Use descriptive comments like “Volume”, “Filter”, or “Send A” to identify controls quickly in your configuration.

Dead Zone

An expanded area around the center position of an analog control that outputs a constant center value (e.g., 64 for a 0-127 range). Dead zones are useful for:

Parameters requiring a reliable neutral position (pan, EQ, balance)
Controls without physical center detents
Preventing accidental value changes when targeting the middle value

Configure dead zone size in the Analog component settings.

Feedback

The visual response from LEDs on your controller based on incoming MIDI messages. Feedback creates a two-way communication loop:

You move a control, sending MIDI to your software
Your software processes the change
Your software sends MIDI back to your controller
The LED updates to reflect the current parameter state

Feedback ensures your controller always displays the true state of your software’s parameters, even when values change from automation or other sources. See Feedback for configuration details.

Hardware ID (HW ID)

A unique numerical identifier for each component in your controller, displayed in the top-left corner of every card. Hardware IDs are fixed and cannot be changed - they correspond to the physical position of each component in your controller’s circuit design.

Takeover Mode

Determines how analog components (faders, pots, joysticks) behave when their physical position does not match the current parameter value. This commonly occurs when:

Switching between banks
The parameter was changed in your DAW
The controller was just powered on

Mode	Behavior
None	Incoming values do not affect component behavior; immediate control
Pick-Up	Component does not send messages until its physical position matches the current value
Value Scaling	Component sends messages immediately, smoothly converging toward the current value

Value to Color

A feedback color mode where the LED color changes based on the received MIDI value. Each value (0-127) maps to a specific color from a palette of 128 colors. This mode is particularly useful for:

Ableton Live clip matrix status
Multi-state parameters
Track arm/solo/mute indicators
Creative visual feedback

Value to Intensity

A feedback feature (firmware v0.20+) that adjusts LED brightness based on incoming MIDI values. Configure a dedicated MIDI channel for intensity control in Controller Options.

Hardware Terms

DIN5 (MIDI Port)

The traditional 5-pin circular MIDI connector used for hardware MIDI connections. In Kilowhat, “MIDI” port refers to the DIN5 connection, as opposed to USB MIDI.

Encoder

A rotary control that can be turned continuously. Yaeltex encoders consist of two parts:

Part	Function
Rotary	The turning action, sends MIDI when rotated
Switch	Pressing down on the encoder, sends separate MIDI messages

Encoders can operate in absolute mode (tracking position between min/max) or relative modes (sending increment/decrement values). See Encoders for complete configuration options.

Endless Encoder

An encoder without fixed endpoints that can rotate continuously in either direction. Most Yaeltex encoders are endless encoders, ideal for relative mode operation where there is no physical stop at minimum or maximum values.

Expression Pedal

An external foot-controlled analog input that connects to your controller. Expression pedals send continuous values based on pedal position, typically used for volume swells, wah effects, or parameter morphing.

Fader

A linear sliding control that moves along a straight track. Faders output continuous values based on their physical position and are commonly used for volume, crossfade, and mixing applications. Configure faders in the Analog section.

Joystick

A two-axis analog input that can move in any direction. Each axis (X and Y) can be configured independently to send different MIDI messages. Joysticks often use:

Dead Zone: For reliable center position
Split Mode: To divide each axis into two separate controls

LED Ring

A circular array of LEDs surrounding an encoder that displays the current value visually. LED rings support multiple display modes:

Mode	Description
Fill	LEDs light from minimum to current value
Spot	Single LED indicates current position
Mirror	LEDs fill symmetrically from center
Pivot	LEDs extend from center based on value direction

Potentiometer (Pot)

A rotary control with fixed endpoints (unlike an endless encoder). Pots have a minimum and maximum physical position, making them ideal for absolute value control. Configure pots in the Analog section.

Additional Terms

7-bit Resolution

Standard MIDI resolution providing 128 discrete values (0-127). Used by NOTE velocity, CC values, and Program Change numbers. Sufficient for most control applications but may produce audible stepping on sensitive parameters.

14-bit Resolution

High-resolution MIDI providing 16,384 discrete values (0-16383). Available through NRPN, RPN, and Pitch Bend messages. Use 14-bit resolution for:

Filter cutoff and resonance
Fine pitch control
Any parameter where smooth transitions are critical

Acceleration

Encoder speed sensitivity where faster rotation produces larger value changes. Kilowhat offers three acceleration levels:

Level	Description
Acceleration 1	Light sensitivity, subtle speed response
Acceleration 2	Medium sensitivity, balanced response
Acceleration 3	Heavy sensitivity, large jumps at high speed

Channel

MIDI channels (1-16) allow multiple devices or instrument parts to communicate independently over the same connection. Each component can be assigned to any channel, and different banks can use different channel assignments.

Fixed Rate

Encoder speed mode that ignores rotation velocity, providing consistent value increments regardless of how fast you turn. Available in three speeds (Fixed 1, 2, 3) for slow, medium, and fast increment rates.

Local Feedback

Feedback source setting where LEDs respond only to the component’s own actions, without waiting for external MIDI confirmation. Use Local feedback for:

Standalone operation without connected software
Immediate visual response
Situations where external feedback is not available

MIDI Merge

A routing feature that combines MIDI messages from multiple sources. Your controller can merge incoming MIDI (from keyboards, other controllers) with its own messages and send everything to a single output.

Momentary

Button behavior where the ON state is active only while the button is held. Releasing the button returns to the OFF state. Compare with Toggle.

Remote Banks

A feature that links bank changes to Program Change messages. When enabled:

Changing banks sends a PC message on the configured channel
Receiving a PC message on that channel switches to the corresponding bank

Useful for synchronized bank changes across multiple controllers or automation-driven bank switching.

Split Mode

An analog component mode that divides a single control into two halves, each sending to different MIDI channels:

First half: Sends on channel 15 (configurable), values from 127 down to 0
Second half: Sends on the configured channel, values from 0 up to 127

Ideal for crossfaders, pan controls, or any bipolar parameter with a center neutral point.

Toggle

Button behavior where each press alternates between ON and OFF states. The first press activates, the second press deactivates. Compare with Momentary.

Velocity

The intensity or speed of a note-on event, transmitted as a value from 0-127. Higher velocity typically means louder or more intense sound. In controller applications, velocity often represents button press intensity for pressure-sensitive pads.

MIDI Monitor - Real-time MIDI message viewing
Understanding Cards - Card interface overview
Controller Options - Global controller settings
Banks Overview - Bank configuration and management