Форум гитаристов

Ha ha ha

it's easy:

Here's formula for Major, Minor and Dominant(7) chords:

Major   1  3   5
Minor   1  3b  5
Major7  1  3   5  7

For instance:

C (major understood)

C D EF G A B
1 2 34 5 6 7   so by formula C - 1 3 5 ( C E G )

E--0(E)----------
B--1(C)----------
G--0(G)----------
D--2(E)----------
A--3(C)----------
E--0(E)----------

C Minor 

C D EF G A B
1 2 34 5 6 7  

by formula Cm 1 3b 5 you may wondering how about 3b
it's easy 3=E 3b=Eb or D# so Cm - C D# or Eb G

E--3(G)-----------
B--4(D#)----------
G--5(C)-----------
D--5(G)-----------
A--3(C)-----------
E--X--------------

C7

C D EF G A B  
1 2 34 5 6 7b 

C7 - 1 3 5 7b - C E G Bb 

E---8(C)---------
B---8(G)---------
G---9(E)---------
D---8(Bb)---------
A--10(G)----------
E---8(C)----------

Here is some other formulas

Dominant7 sus4 - 1 4 5 7b
Dominant9      - 1 3 5 7b 9