Question:
Fm7-5/Cb
F#m7-5/C
Ab7+5
Answer:
Enough - this is what i would try since i do not have the song you doing.
you may want to try moving your fingers around if they seem alittle off- check your fingerboard roots and notes. also try:
http://www.guitar-masters.com/ [jazz chord section]
http://gospelmusic.org.uk/resources/chord_chart_big.htm
http://www.chordie.com/chords.php
found the below at: http://www.all-guitar-chords.com/
Fm7-5/Cb - 1x110x
Name: Half-diminished minor 7 chord
Symbols: m7b5, m7-5, ø
Steps: 1-b3-b5-b7
Recommended scales:
Locrian scale
Half Diminished #2(Locrian #2) scale
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F#m7-5/C - 2x220x
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Ab7+5 - 43211x
Name: Augmented triad
Symbols: aug, "+"
Steps: 1-3-#5
Recommended scales:
Lydian Augmented scale
Answer:
In a minor chord, a -5 would mean you do not play the 5. Only in a major or dominant chord does a "-" mean to flat the note.
The "/Cb" and the "/C" are the bass notes for both those chords which in reality is the 5b for these chords anyways. If you have a bass playing with you, you can let him carry it and just play the Fm7-5 and F#m7-5 respectively, but it would most likely sound better if you play it as your root on guitar also.
Whenever you see a "/" in a chord it is refering to what the bass guitar should be playing or the bass root of the chord instead of the natural root of the chord.
That being said, both the first two chords are the same formula and fingering as a bar chord - the formula being a 1-3b-7b/5b - So . . .
Fm7-5/Cb = x21141 = Cb-Eb-Ab-Eb-F
F#m7-5/C = x32252 = C-E-A-E-F#
You could easily complete the chord with adding the bar on the sixth string but that would change the root to the natural root itself which in turn would change the voicing of the chord which might not be the desired effect you want with that "Cb" and "C" bass note - it really depends on how you are picking or strumming it and the song itself and what root you will be emphasing in your strum/pick.
The +5 in the Ab7+5 means your going to add an extra high 5 (no pun intended) in the Ab7 chord - it's really not necessary since the 5 is already in the chord but it does add a nice change of pace voicing to a chord. I use +5 chords a lot as a high peddlepoint to break up chorus and verse when they are virtually the same as in Matt Redman's "Blessed Be Your Name".
The formula is the same with or without the +5 which is 1-3-5-7b So . . .
Ab7 = 431112 = Ab-C-Eb-Ab-C-Gb
Ab7+5 = x31142 = C-Eb-Ab-Eb-Gb
Technically you would want the Ab on the 6th string, but personally I don't have that many fingers so I would leave that to the bass or just drop the +5 if I'm playing solo. Again, that really depends on the voicing of the song itself.
Hope that helps.