Understanding chords

Okay, you now know how to choose a space to navigate in. You also know how to limit the number of allowed notes in that space by choosing a scale and key. And you are able to adjust the note label display as needed. Now let’s examine the last bit that’s missing from the picture : chords.

Like a scale, a chord is defined by a set of intervals. However, the number of notes in this set is typically much lower, with three or four being common.

We can classify chords after the number of notes in them:

monads: single note (or unison)

dyads : have two notes

triads : have three notes

sevenths: have four notes (also known as tetrachords)

quintads : have five notes

In tonespace 2 we support monads, dyads, triads and sevenths only.

You can select a chord in tonespace by setting three parameters. First set the ch filter parameter to All, which lets you choose from all possible chords.

Then set the assist parameter to Play chord if root in key. This will let us play the chord if we click on a cell that is in the current scale/key.

Then set the chord parameter to any of the chords in the combobox. For instance let’s set it to [3] Major:

A major chord is a triad defined by the intervals [0 4 7]. Let’s see what happens when we try to play this chord on our space. To make things easy, set your other parameters as follows :

Note: click also once on the little mouse wheel symbol before the chord combobox. This will become useful in a moment.

Now point your mouse in the space at midi note 60. You should see this :

The grey highlighted cells indicate how your chord maps onto the space. Since the major chord was defined by intervals [0 4 7] and you pointed at midi 60 as root note for the chord (starting note), it will highlight midi notes 60+0, 60+4 and 60+7. The highlights are not only in the grid, but also on the piano keyboard. This makes it really easy to see the relationship between the space cells and the piano keys.

Now press the left mouse button. If tonespace is set up right, you will now hear a major chord. The grey cells and piano keys should become orange too as long as the chord is sounding.

One thing you can spot visually immediately is that the major chord with root note midi 60 (C4) maps nicely onto the C major scale/key. This is no coincidence, since the major chord intervals are a subset of the major scale intervals.

Now move the mouse to midi note 62 (notice how you cannot move it to the black cell midi 61, since this is not part of the scale/key). You will now see these highlights (rest of screen omitted) :

Now we have a problem: the chord does not fit entirely onto the scale/key anymore, since the middle interval maps to a black cell. So if you would play this chord, the middle note would be a forbidden note. Whether that is a problem or not is not a hard rule and depends really on your intention and preferences as a composer, but let’s say for simplicity that you would really like to stick to notes within the selected scale/key. In that case we should change the chord to something else that does fit at that root note.

What could we use then? Well, go back to your chord parameter and select [3] Minor instead of [3] Major. The minor chord is a triad defined by intervals [0 3 7]. Now point again to midi note 62 within the space. That should give you :

Now you can see that this chord does fit into the C major scale/key at that position.

This is one of the uses of tonespace : a visual tool that helps you spot easily how a range of chords map onto a given scale and key. And then shows you how that chord maps back onto a piano keyboard, so you could play it on an external keyboard.