Irish tenor banjo scales
Every scale Irish traditional music actually uses, drawn as GDAE tab in first position - all twelve charts on this one page. Together they cover 2595 of the 2701 tunes on this site.
Why scales are the whole trick
Watch a session and somebody is always playing notes that are not the tune: runs, variations, little answers to the melody. They are not reading anything and they are not guessing. Every tune lives in one scale, the accompanist's chords are built from the same seven notes, and so any note of the scale fits over any chord in the tune. Learn the shape and you have every note of every tune in that key before you have heard it. On a GDAE instrument the shapes are unusually kind: tuning in fifths means one finger pattern per scale, and almost everything sits below the fifth fret - the odd 6 or 7 in the charts is the pinky note that matches the next open string.
The twelve scales, one chart each
G major
985 tunes on this siteChords: G, C, Em + Am, D, D7
Tunes in G major, and its FAQD major
756 tunes on this siteChords: D, G, Bm + Em, A7
Tunes in D major, and its FAQA major
257 tunes on this siteChords: A, D, E + F#m, E7
Tunes in A major, and its FAQC major
78 tunes on this siteChords: C, F, G + Am, Dm, G7
Tunes in C major, and its FAQE minor
142 tunes on this siteChords: Em, D, G + C, Am
Tunes in E minor, and its FAQA minor
127 tunes on this siteChords: Am, G, C + F, Dm, Em
Tunes in A minor, and its FAQG minor
93 tunes on this siteChords: Gm, F, Bb + Cm, Dm, Eb
Tunes in G minor, and its FAQD minor
46 tunes on this siteChords: Dm, Am, C + Bb, F
Tunes in D minor, and its FAQA dorian
45 tunes on this siteChords: Am, G, C + Em, D
Tunes in A dorian, and its FAQE dorian
5 tunes on this siteChords: Em, D, G + C, Bm, A
Tunes in E dorian, and its FAQD mixolydian
35 tunes on this siteChords: D, C, Am + Bm
Tunes in D mixolydian, and its FAQA mixolydian
26 tunes on this siteChords: A, G, Em + D
Tunes in A mixolydian, and its FAQPentatonic shapes
Five-note scales: the major and minor pentatonics drop the two notes most likely to clash, which makes them the safe-notes vocabulary for playing over tunes you half know. Nearly everything written about them for banjo is five-string bluegrass, so the GDAE charts get a page of their own: G and D major pentatonic, E and A minor pentatonic, all in first position.
Modes, in one paragraph
A mode is a scale that treats a different note as home. A dorian uses exactly the notes of G major but centres on A; D mixolydian is D major with the seventh flattened. Irish music leans on these two modes constantly, which is why so many tunes sound minor without being minor and why the "wrong" chord a step below home keeps appearing behind big reels. Each chart above says which chords carry its key, so the fingering you already know does double duty.
Questions about scales
G major and D major first: between them they cover 1741 of the 2701 tunes on this site. Then A dorian and E minor for the minor-sounding tunes, and the mixolydian modes as you meet them. Every chart above sits in first position, almost all of it below the fifth fret.
This page is it. Press Print and the charts come out on their own, without the navigation or anything else around them, on paper or to PDF.
They stay inside the tune's own scale. A tune in G uses the seven notes of the G major scale, and the backer's chords are built from those same notes, so any note from the scale fits over any chord in the tune. What sounds like free improvisation is ornamentation and variation that never leaves the scale.
A mode is a scale that centres on a different note. A dorian uses exactly the notes of G major but treats A as home, which changes the whole colour from bright to dark without changing a single note. Irish music leans on dorian and mixolydian modes more than almost any other living tradition, which is why so many tunes sound minor without being minor.
Yes: the five-note shapes work on any instrument, and on GDAE tuning they sit in first position like everything else. They are on their own page - pentatonic scales for tenor banjo - because tunes are not written "in" a pentatonic; it is a practice and safe-notes vocabulary rather than a key.
The notes are identical and so is the GDAE tuning logic: instruments tuned in fifths share fingering patterns, so a scale learned on tenor banjo transfers to fiddle, mandolin, octave mandola and tenor banjo. Only the bouzouki's GDAD top string changes anything.