The aim in designing nimbu was to develop a real-time arranger that comes as close as possible to the original in musical terms. In this context, the original is represented by a good MIDI file. To achieve this aim, an arranger must have the following two characteristics.

1. The arranger must be able to play the matching tensions to the chords

The accompaniment has the same tones available as the melody. To each chord in a key, all tones of the key can be played melodically and almost all tones can be played chordally. This applies equally to melody and accompaniment. Chords alone are not sufficient for accompaniment. No real backing band plays only chord tones. Nor can generated tensions in the styles compensate for this deficit, because they usually do not fit. The accompanying instruments in MIDI files play characteristic tensions. An arranger must also have this ability.



2. The arranger must support time signature changes

Many hits and thus many MIDI files change time signature. Therefore, the time signature structure can only be transferred to the arranger with the support of time signature changes.

In addition, the following overarching objective had to be taken into account.

3. The music of the arranger must be transparent and easy to edit interactively

Without editing capabilities, it is impossible to do justice to the diversity of music. This additional goal requires that the arranger's transpositions be based on the rules of music, which is only very restricted the case when reduced to chords.

Most of today's arrangers do not even have one of the first two properties. With these three musical properties, nimbu far surpasses today's arrangers. These three properties of nimbu result in an almost indescribable wealth of musical playing and editing possibilities, which can only be briefly touched upon here.


nimbu is the arranger that transposes chord scales instead of chords. The tensions of the chord scales give your accompaniment the authentic sound of a band.


When you play, chord recognition, chord resolution and sequence control take place in real time. Chord scales with at least 7 notes are assigned to the chords you play in order to play all available tones and thus also the characteristic tension tones. Realistic, authentic accompaniments are produced.

Tones of the Key     =      Available Tones     =      Tone Supply     =      Chord Scale    =     Chord Tones    +    Tension Tones

Using the full tone supply of the chord scales, nimbu calculates title-related accompaniments from MIDI files. If you play these accompaniments with the original chords (i.e. with the same harmony progression as in the MIDI file), they are hardly distinguishable from the MIDI file. Of course, you can also play these accompaniments with other chords by switching to chords while playing and thus reducing your accompaniment to chord tones in real time.

You can also play backing rhythms (styles) developed for YAMAHA® keyboards. You can edit your styles at any level and even export them to play on a YAMAHA® arranger keyboard.

nimbu is based internally on note events, which are notated in chord scales steps and resolved into notes based on the chords and their chord scales played, so that the musical context is known at all times. No simple MIDI note on and off messages. All the music is open and transparent.

We describe the musical basics in   More Tones, More Music.

nimbu offers you two integrated sound modules and all common MIDI and audio interfaces for setting up a complete arranger workstation. Whether virtual instruments or sound module, whether tablet or MIDI pad, the configuration and design of the system is very flexible. You can find the requirements here.

Instruments and Tracks

The music in nimbu is stored either in the form of notes in the tracks or in the form of scale steps in the instruments. The instruments form your accompaniment, which you play with your left hand. Both the tracks and the instruments are divided into the categories Drum 1, Drum 2, Bass, Chord 1 to Chord 8. For the melody voices the Melo 1 and 2 categories are also available in the tracks. Notes and scale steps are time-controlled events in nimbu.

Each category from bass 1 to melody 2 is assigned a corresponding instrument (voice), which can be changed spontaneously via one-touch switches while playing.

In addition, tempo changes, time signature changes, chords and so-called control and program changes, as well as markers are stored centrally in the Event Track category. The Timing Design and Dynamic Design categories are available for time and velocity accentuations. The lyrics are stored in the Lyric Track. All instruments and tracks are saved in a session file.

Instruments	Event Type	Tracks	Event Type
Drum 1	Drum	Drum 1	Notes
Drum 2	Drum	Drum 2	Notes
Bass	Scale Steps	Bass	Notes
Chord 1	Scale Steps	Chord 1	Notes
.....	.....	.....	.....
Chord 8	Scale Steps	Chord 8	Notes
		Melo 1	Notes
		Melo 2	Notes
		Event  Track	Chords +  Controls
		Velocity   Design	Dynamic   Progression
		Groove  Design	Micro Timing  Progression
		Lyrics	Text

If you are already playing with Arranger or auto accompaniment, you will be familiar with a lot of this. Remember, however, that you are playing with a larger tone supply. The Chord 1 to 8 instruments in nimbu play both chord and tension tones, so that they can take over all the functions of the usual Bass, Chord 1 & 2, Pad and Phrase 1 & 2 instruments.

Design and Features

The nimbu instruments contain the accompaniment, which is notated in scale steps. Their actual tones only result from the chords that you play on the left of your keyboard or that you specify in the event tack. More precisely, from the chord scales that are assigned to the chords you play. Of course, this does not apply to the drums Drum 1 and Drum 2, whose events are assigned directly to the percussion instruments.

When playing, the nimbu instruments are transposed with the chords played or their chord scales. The assignments of the chord scales to the chords played are defined separately for each of the 24 nimbu sections (in the event of deviations from the standard scales). When importing MIDI files, the chords are calculated and the chord scales are assigned automatically. When importing styles, the source chords of the style are adopted and assigned to nimbu standard chord scales.

As nimbu transposes chord scales, the instruments' range of tones is not limited in any way. The time signature can change within an accompaniment in nimbu, so that there are no restrictions in terms of time either. Fill-ins with several bars are also supported. Transposable accompaniments for the auto accompaniment are created from the tracks of a MIDI file. The accompaniments of the auto accompaniment can in turn be recorded in tracks while playing the chords and then saved as a MIDI file.

In contrast, the events of the tracks are fixed in terms of their information or pitch during playback. The tracks are played like a tape. They contain notes and chords on the one hand and information for the sequence control on the other. The nimbu tracks with the notes are primarily used for importing and exporting MIDI files and styles or for recording from the keyboard or for playback and demonstration functions.

The session is controlled via the keyboard keys, a touch screen or MIDI controllers or MIDI pads as well as via the EventTrack. More than a hundred different nimbu switches and controllers are available for this purpose. The session panel displays the current status and can also be used conveniently via a touch screen.

Each nimbu session consists of 24 sections. In accompaniment mode, each of these sections can record an independent accompaniment or style, all of which are located in the main memory and can be controlled in real time. In composition mode, the accompaniment is put together from these sections like in a construction kit, whereby inheritance functions for basic rhythms are also available. The order in which the sections are played is determined by the sequence definition and direct control on the keyboard. Playing the chords with transposition of the accompaniment is identical in accompaniment and composition mode.
All events in the various sections can also be copied and pasted via the clipboard.

Markers such as Intro A, Main B etc. are jumped to directly across the boundaries of a style, e.g. via Bridge A to D, whereby the instrument setup is adopted "on the fly". nimbu also allows several time signatures and fill-ins with several bars within an accompaniment or within a marker.

Furthermore, nimbu also recognises so-called NoMarkers in order to be able to close certain marker ranges in accompaniments that have been calculated from MIDI files. The marker ranges therefore do not have to be adjacent in nimbu.

With the timing and dynamics design, further temporal and dynamic accentuations are incorporated into the session. These two designs additionally modulate the instruments in a session in a concerted manner to create even more drive.

You can edit all events in a variety of ways, just like in a word processing programme. If nimbu plays in a loop, you can build up the accompaniment successively across all instruments, while the chords are played by you or specified in the event track. Undo/redo functions and the indexing of entire event sections are a matter of course.

When playing, the various events are processed in real time. The graphical representation of the playing of all events also takes place in real time, so that you can follow your song at every level. nimbu is not a single-window application, i.e. the temporal progression of melody, harmony, accompanying instruments and the controls during playing is displayed synchronously in all open windows at the same time.

nimbu for Newcomers

To practise, you let nimbu play certain categories and call up specific windows that support you in practising. nimbu shows you every level of your music in real time. This is an advantage when the accompaniment is calculated from a MIDI file. However, this information can also be specified by you for a style. Here are a few examples:

If you only want to practice the melody at first, let nimbu play the chords from the event track. nimbu will show you the melody keys to be played while practicing.

Wenn Sie nur das Harmoniespiel üben wollen, können Sie Nimbu die Melodie aus der Melodiespur spielen lassen. Auch hier zeigt Ihnen nimbu beim Üben die zu spielenden Akkordtasten.

nimbu shows you the keys and chords to be played in real time. nimbu even draws your played note events below the note events of the melody to be played, so you can compare your played notes directly with the notes of the melody. While playing, you can see very clearly where your notes are playing too early or too late. You can also view these recordings after playing.

Even when improvising, you can see in real time the respective tone supply that is musically available to you.

You can find further details under Playing Keyboard made easy.

nimbu at a glance

For a functional overview of the 3 nimbu editions with corresponding maximum values click here.

Graphical User Interface

If you want to get a first impression of the graphical user interface, then you should read on here.

nimbu - because backing bands play tensions.   Here is our offer.


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