Key concepts

A session view or clip launcher is a user interface tailored to Non-linear music production where musical elements are arranged in a grid of rows and columns. Each cell typically holds a single musical element, and users can trigger, loop, and record these elements in real time, often for live performance or experimental composition.

Playtime is described as a session view.

In Playtime, a matrix is the top-level structure. It is fundamentally a two-dimensional grid of slots that hold clips, arranged in columns and rows. On a broader level, the matrix functions as a container, comparable to a project in REAPER, and includes various settings.

Each instance of Helgobox can load a single Playtime matrix. By default, it contains no matrix, so it must be created explicitly. This approach ensures that Helgobox instances dedicated solely to ReaLearn don’t consume any Playtime-related CPU or memory resources - you only "pay for what you use".

In Playtime, a column refers to a group of slots, typically arranged vertically.

A column is linked to a Column track, which is used for playing back the clips it contains.

By default, only one slot in a column plays at a time, but Playtime also allows for simultaneous playback of multiple slots in the same column.

In practice, each column typically represents a single musical instrument or vocal track.

A column track is a normal REAPER track linked to a Playtime Column.

Like a Column, a row refers to a group of slots, but arranged horizontally.

A row is always associated with a Scene, so the terms are often used interchangeably.

In practice, each row often represents a part within a larger song structure.

In Playtime, a slot is a fixed position in the matrix that can hold clips and can be played back or stopped. Each slot functions as a mini audio player.

Typically, a slot contains a single clip, but Playtime allows multiple clips in a slot to play back simultaneously. In such cases, the Clip start timing of each individual clip is relevant. The slot itself does not contain any settings.

In Playtime, a clip is a container that holds a snippet of audio or MIDI, referred to as the Source, and can be configured in various ways. It is somewhat comparable to an item in REAPER.

In practice, a clip is often a short, beat-aligned loop.

In Playtime, a source represents the raw media data.

In Playtime, a scene denotes a segment within a larger song structure. It corresponds to a Row.

Each scene features a play button that triggers playback for all slots in that row.

By default, a scene encompasses all slots of the row. However, Playtime allows a Column to opt out of scene playback if desired.

A matrix sequence is a recording of interactions with the Matrix.

Playtime lets you record matrix interactions into a sequence. Each sequence is saved as part of the matrix. Later, you can play it back, directly in Playtime.

Most importantly, a sequence can be "written down" to a REAPER Arrangement at any time: All clips occurrences are placed on column tracks as REAPER items. This is often done at the point in the song creation process, when you are satisfied with the sequence and want to transition to linear arranging on the REAPER project timeline.

In Playtime, an arrangement typically refers to a set of REAPER items on the column tracks of the matrix, making it suitable for Linear music production.

An arrangement can be created …​

Playtime is not necessary to play the arrangement back. You can share a REAPER project containing an arrangement written via Playtime with someone who doesn’t own Playtime, and they will still able to play it back! In practice, however, it’s recommended to keep Playtime as part of the project, to freely switch between Session view / Clip launcher and Arrangement.

The clip start timing is a configuration property for a Clip. Because of its importance, it’s mentioned here already as a key concept.

The start timing decides when a clip actually starts to be played back, after you have triggered its playback.

By default, the start timing is 1 bar, which means that the clip will start playing at the beginning of the next bar. This is what makes everything in-sync You can change that to arbitrary quantizations, such as 2 quarter notes or 3 bars. Alternatively,

A bar, also known as a measure, is a section of music that contains a specific number of beats, as defined by the Time signature. It helps organize the music into manageable parts, making it easier for musicians to read and perform. For example, in a 4/4 time signature, each bar has four beats.

A beat is the basic unit of time in music, serving as the rhythmic foundation for a piece. It’s what you tap your foot to when listening to a song. Beats are grouped together in bars and can vary in length and speed, creating different feels and tempos in music.

A time signature in music is a way to show how beats are grouped in a piece. It tells you how many beats are in each Bar and which type of note gets one beat. For example, in a 3/4 time signature, there are three beats per bar, and each beat is a quarter note. It helps musicians understand the rhythm and feel of the music.

In the context of rhythmical music, in sync means that everything is synchronized and the timing aligns correctly.

When you play loops in Playtime, you typically want them to be in sync with each other and with all other rhythmical material on the reference timeline.

To achieve this synchronization, the following conditions must be met:

When using Playtime’s default settings, both conditions are automatically met.

A quantization in Playtime defines when an event should occur, such as the start of clip playback or the stop of a recording. It divides the Timeline into equal time intervals, ensuring that the event occurs only at the beginning of each interval.

A quantization is typically expressed as a Time signature.

In Playtime, a timeline refers to the concept of time divided into bars and beats, featuring a continuously advancing playhead and a current tempo.

One Matrix has exactly one reference timeline at a given point in time. Quantized events such as start of Clip playback are aligned to this reference timeline.