Chord "Deux" Jour Challenge: A7 and C#m7b5

The Chord "Deux" Jour Challenge means learning or expanding upon two chords per day. Check the full list here.

Each chord "map" attempts to appeal to both beginners and intermediate/advanced guitarists and keyboardists. Simple chord voicings for beginners are provided with the following finger system:

1 index finger
2 middle finger
3 ring finger
4 little finger
o play open string
x do not play open string
( bar one finger over more than one string
T that rare occasion that I recommend you use your thumb to fret a note

Today, we have the "children" of C#dim:  A7 and C#m7b5. They are "children" in the sense that they contain C#dim's notes (C#-E-G), can possibly be a substitute chord for C#dim, yet neither chord are quite C#dim (due to an extra note for each chord).

A major (minor) 7th, or A dominant 7th -- A7:

Guitarists, there's more than one way to fret this chord shape. If you're using this chord for a measure or two, I recommend using your index and middle fingers. If you're changing from A7 to A, and vice versa, I would probably recommend you use your index, middle, and ring fingers for a traditional A chord shape. Then lift your middle finger to fret the A7.  Basically, use logical finger placement, and use comfortable finger placement.

Keyboardists, if A major and C#dim mated ... in fact, try A with your left hand and C#dim with your right. Play both chords simultaneously. Then play C#dim with your left, and A with your right.

C-sharp minor (minor) 7th flattened 5th, or C#m7b5:

Guitarists, if you remember Bm7b5, move two frets higher.

Keyboardists, if Em and C#dim mated ... in fact, try C#dim with your left hand and Em with your right. Play both chords simultaneously. Then play Em with your left, and C#dim with your right.

Two more tomorrow! Cheers!