Instrumaps

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Diatonic Blues Harp — 5 Positions — Bends & Blues Scale

Select the key the song is in:

Song key: C (rel. minor: Am)
1st PositionStraight Harp
Grab C harp
Ionian (Major)major
Most Common
2nd PositionCross Harp
▼ VIEWING
Grab F harp
Mixolydian → Bluesdominant/blues
3rd Position3rd Position
Grab Bb/A# harp
Dorian (Minor)minor
4th Position4th Position
Grab Eb/D# harp
Aeolian (Nat. Minor)minor
5th Position5th Position
Grab Ab/G# harp
Phrygianminor/exotic
F Harmonica2nd Pos — Key of C
HomeIn scaleNot in scaleDashed = use sparingly
↑ Blow (breathe out) ↑
F
3rd
1
G
5th
F#'
4th
A
2
C
1st
B'
Bb''
6th
C
1st
3
E
Eb'
2nd
D''
Db'''
F
3rd
4
G
5th
F#'
4th
A
5
Bb
6th
C
1st
6
D
Db'
F
3rd
7
E
Ab'
A
8
G
5th
B'
C
1st
9
Bb
6th
E'
Eb''
2nd
F
3rd
10
D
↓ Draw (breathe in) ↓
Resolve to draw 2. Live in the draw notes — they carry the blues. The blue bends are your blue notes (draw 3 bend = ♭3, essential). Blow notes are available but use them as passing tones, not home base.

Reading the Bend Notation

Db'↓ = draw bend, 1 semitone down (single bend)
F''↓ = draw bend, 2 semitones down (double bend)
Ab'''↓ = draw bend, 3 semitones down (triple — hole 3 only)
Eb'↑ = blow bend, 1 semitone down (holes 8–10)

In the upper register (holes 7–10), the blow note is higher than the draw note — so bends go on the blow side. Deeper bends = harder technique.

The Algorithm

Blues (2nd pos): Song key → count up a 4th → that's your harp.
Song in C? → C → D → E F → grab F harp.

Major (1st pos): Song key = harp key. Simple.
Song in C? → grab C harp.

Minor (3rd pos): Song key → count down a whole step → that's your harp.
Song in Cm? → down from C Bb → grab Bb harp.

Full Matrix — All 12 Harps × 5 Positions

Harp1st
Ionian
2nd
Mixolydian
/ Blues
3rd
Dorian
4th
Aeolian
5th
Phrygian
CC
Am
GDA
C
E
DbDb
Bbm
AbEbBb
Db
F
DD
Bm
AEB
D
F#
EbEb
Cm
BbFC
Eb
G
EE
Dbm
BF#Db
E
Ab
FF
Dm
CGD
F
A
F#F#
Ebm
DbAbEb
F#
Bb
GG
Em
DAE
G
B
AbAb
Fm
EbBbF
Ab
C
AA
F#m
EBF#
A
Db
BbBb
Gm
FCG
Bb
D
BB
Abm
F#DbAb
B
Eb

Read as: "[Harp] in [position] → play in [key]" · small line on 1st / 4th = relative pair (same notes: C and Am, etc.)

Select any position card to update the harmonica and piano diagrams