Theory quick start (4 minutes).

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This guide won’t cover theory per-se. Interactive content instead presents theory (such as our blog and lesson content). This guide covers what support is built into emuso for visually reminding you of intervals, by typing “i” and “=”, and using mouse interactions on-“instrument”.



If you need a high-level reminder about what intervals are, and their importance, see Music 101 (part 2)

Chords and scales are made up of intervals.  If you know the interval shapes, you can use that to locate each chord or scale note, and these are quick to learn.  If you remember what the intervals are, by “name” (such as “b3” or “5”), you can recall this info when practicing rather than just playing a chord or scale shape with no regard to what the shape means. Knowing these,  you will have much less to learn and remember (as opposed to learning the note names, since these change if that shape is moved, whereas intervals within the shape don’t). This means you will be better armed for note-choice when improvising or writing songs if your practice has drilled in how to locate these.


What you will learn

Notes (circles) on instrument can be labelled with interval information, or note names. A colour scheme is used to denote the interval, by colouring the rim of the note’s circle. These will help you quickly remember how to locate intervals on-“instrument”. You’ll learn about these next. You’ll learn how to use the ALT key to generate chords by hovering the mouse over scale notes on-instrument. Finally you’ll learn how to set up your own colour scheme.

Visual representation of intervals

This next interaction creates a block of 16 notes along the bass E string (6th string), starting at the anchor located at fret zero.

  1. Notice the notes are labelled 0 to 15 starting at the anchor at fret 0, as these notes are various semitones ABOVE the anchor note. The absolute semitone distance from the anchor to the note is shown in the label. Adjacent frets on the same string produce notes that are a semitone apart.
  2. Click”Reroot” on the interval and pitch strip. Left click on the note at fret 12 on the bass string. This note is now the anchor. Interval distances are now measured from the anchor here.
  3. Notice the labelling is now showing negative values below fret 12, as these notes are various semitones LOWER than the anchor note
  4. Click “Toolkit” and click on the “Octave” button. Dim red circles appear at all octaves of the anchor.
  5. CTL-left click on each of these dim red circles, to relocate the anchor. Since this is a scale fragment laid out along one string, some of the fragment may “fall-off” the string. Notice the labelling each time.
  6. Try dragging the anchor with the left mouse button held down, especially towards the nut, and watch what happens.
  7. Click “Toolkit” again to exit the toolkit. The scale fragment present on entry to the Toolkit is restored.

When improvising, we never think of semitones above or below. This next interaction shows a different form of labelling … “semitone distance from the nearest lower octave of the anchor“. When improvising, we want to be aware of this, though in a slightly different form (“location of interval symbol from the nearest lower octave of the anchor“) coming up shortly.

Make sure you have exited the Toolkit before you try this.

  1. Notice the labelling is now showing values in the range 0 to 11, showing the semitone distance from the nearest lower octave of the anchor (12 semitones lower). This is visually obvious if you look at frets 11,12 and 13 on the 6th string. Notice that the labels 0, 1, 2, and 3, appear twice.  Notes with the same label are the same notes, in different octaves from the anchor.  The anchor is at the nut.
  2. Click “Reroot” and left-click on the 0’th fret (the nut) of the 1st string. The anchor is now there (but it is unoccupied).  Where the anchor was and is are both the note E, in different octaves. The labelling is unaffected because the anchor is located at an octave of where it was before the reroot.  Left-drag the anchor along the 1st string towards the body, and then back to fret 0.  The scale fragment relocates, maintaining its relationship with the anchor (its lowest note is always 2 octaves below the anchor).
  3. Make sure the anchor is on the 1st string at fret 0.  Click “Reroot” and left-click on the 9th fret (the nut) of the 3rd string (which is also the note E in a different octave).  Because there is no note occupying this new location, the anchor is empty (reroot never creates a note).
  4. Left click on the 9th fret and the 10th fret of the 3rd string, creating notes there, including a note at the anchor at the 9th fret.
  5. Left-drag the anchor left and right, along its string, and watch what happens. Observe how the scale fragment “falls off”, and reappears.  The labelling is always relative to the anchor.
  6. Left-drag the anchor towards the bass string, and observe how the scale fragment “falls off”, and reappears when you Left-drag the anchor towards the treble string.  It is impossible to drag the anchor off-instrument.
  7. Type “=”  until you see labels like “b3”, “b5” appear on the notes. “b3” is the theoretical symbol for a note 3 semitones above the nearest lower anchor. “b5” equates to a note 6 semiones above the nearest lower anchor.
  8. Left-drag the anchor again. Observe how the same symbols appear relative to the nearest lower anchor.

Now let’s look at a scale. You’ll be asked to select (right-click) all the “b3″s that you can see, and then to delete pitch classes (CTL+right-click) for “2” and “b6” to convert a scale from Aeolian to minor pentatonic


You can choose how you want notes to be labelled on-instrument. At a minimum, the note can be set to black with a white rim (no information).

Emuso uses a colour-scheme to denote different intervals. The note can appear black with coloured rims (a slight reminder of the intervals). The following additional information can be presented withing the note’s circle.

  • semitones
  • absolute semitones
  • interval symbols per octave
  • note names

You can switch between these, repeatedly pressing “i” (make sure the mouse is in the same pane as the instrument). The labelling you need to become familiar with is “interval symbols per octave”, as you practice learning scales and chords.

You can also use “=” to switch between semitones in the range 0 – 11. and interval symbols per octave.

For example, here you will see how the same interval “b3” occurs both in the scale and a chord found in that scale. Knowing this, you can think “I’ll land on the b3 when improvising with this scale over this chord”. After a while, you just know this is a good landing note without especially thinking it’s a b3. But, during directed practice, you absolutely must recognise it is a “b3”, for example.

Using the mouse and ALT- key for basic chord and scale discovery

You can move the mouse over a scale note, with no mouse button held down, but wth the ALT key held down, and have the notes of a chord highlighted, rooted at that scale note.  There may be more than one highlighted note on a string, as this support shows some locations that can supply the chord notes, as opposed to showing chord voicings (which have at most one note per string).  This is useful when thinking about chord tones found in a scale shape.

As an example, here is an interaction that creates a “Dorian” scale.

  1. Set the Play Construct gadget to “Harmonic”.
  2. Type CTL+Shift+3.  This will cause 3-note chords (named triads) to be generated. Notice a message appears at the top of emuso, slightly left of the guitar along with the chord type.
  3. Hold down the ALT key and move (don’t click) the mouse over each of the scale notes in turn.  We refer to this as “hover over a note”.  Watch and listen. This shows three-note chords (triads).

You can get emuso to create from three to seven note “chords” (not chord voicings which only have one note per string).  Don’t worry about the names, but listen and watch.  Notice as you make your choice, a message appears above the instrument confirming your choice.   Only the notes visible are used, so it may be impossible to create the full chord. You choose from one of the following, and then use ALT as above.  Emuso will suppress some “chords” if they are not musically useful (don’t worry for now).

  1. Type CTL+Shift+3 for 3 note chords (known as triads)
  2. Type CTL+Shift+4 for 4 note chords (known as sevenths)
  3. Type CTL+Shift+5 for 5 note chords (known as ninths)
  4. Type CTL+Shift+6 for 6 note chords (known as elevenths)
  5. Type CTL+Shift+7 for 7 note chords (known as thirteenths)
  6. Type CTL+Shift+8 for 3 note “quartal” chords
  7. Type CTL+Shift+9 for 4 note “quartal” chords

Changing the colour scheme for intervals

The “Colour picker” tool (shown below, click to enlarge (when the lesson is full-screen)) lets you choose colours for the different intervals.

It appears when you select “Settings > Customise fretboard and interval colours…” from the menu bar at the top left of emuso. It can be repositioned by left-dragging the mouse anywhere in its black background. Notice how the colours shown on the tool match the colours shown on the pitch and interval strip, and the colours used on notes on the instrument.


Let’s change the colour of the interval b3.

  1. Select Settings > Customise fretboard and interval colours…
  2. Enter the Toolkit, and choose “Min Triad” from the Chord menu
  3. Click on the button labelled “b3” in the picker.  Its appearance changes.
  4. At the bottom right of the picker, click on the drop down arrow showing next to label “White”.  A colour palette appears.
  5. Choose a colour, and watch how the circle rim on the note labelled “b3” changes to match, as does the interval strip’s “b3” colour.
  6. If you want to change the colour of the anchor when its unoccupied, use the “Anchor” button in the picker to do this.
  7. Use “Reset” in the picker to revert to the colour schem emuso comes with.

You can also change the colour of text showing inside the circles representing notes, with the colour picker.

  1. Click on “Instrument Label” and select a colour.

You can change the background colour of the guitar fretboard.

  1. Click on “Fretboard” and select a colour.


What you have learned

You’ve learned that typing “i” repeatedly changes the labelling of notes, with options for semitones in the range 0-11, interval symbols (e.g. “b3”), unrestricted semitones (negative values or values greater than 11), and note names.  Type “=” to switch between semitones in the range 0-11 and interval symbols.



You’ll learn about the  help system built into emuso, which includes videos that can be activated from clicking on menu items and buttons and so, explaining what these do.  The help system also includes user-guides.

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