e |----------------------|
b |----------------------|
g |----------------------|
d |----------------------|
a |----------------------|
e |----------------------|
drop d tuning
e |----------------------|
b |----------------------|
g |----------------------|
d |----------------------|
a |----------------------|
d |----------------------|
down half step tuning
Eb |----------------------|
Bb |----------------------|
Gb |----------------------|
Db |----------------------|
Ab |----------------------|
Eb |----------------------|