Another--not so dumb?-- Theory Question

[B.T.]

It's been 20 years or so since I picked up my theory book to brush-up and have maybe, to you guys, a dumb question. In a standard "pop" music book from the local music store that has songs in it with voice, piano (treble/bass clefs)and chords written above the melody line there is a tune that has a chord---Am6--above the melody note of A. The treble clef has a stacked triad of C (bottom), E (middle), and A (top) and the bass clef has one note--the F#. Question: I have seen this tune in two different books--one with an Am6 chord and one with an F#m7b5 (which I don't remember how it was "stacked"). I realize that they are the same chord and what makes them "different" would be whatever is the bass note. Putting an Am6 on the above description doesn't fit--exactly--either of these two chords in any of their inversions. I know this is very anal-retentive but was just wondering if I am missing anything theory-wise. Either chord works fine in any of their inversions but is putting an Am6 over the chord just the easiest and not the most accurate with the way the notes are written on the clefs?

[steve the artguy]

since no one bit on this, I'll tell what I think.

 

It's impossible to tell, really, without seeing the chord in context. By itself it would definitely seem to be an F# chord, but perhaps it's just functioning as a passing chord, or an Am over a bass line which happens to be on an F# at that point.

 

Calling it an Am6 is probably a reach, harmonically.

 

-steve the artguy

[Dan South]

They are the same chord.

 

Am6: A C E F#

 

F#m7b5: F# A C E

 

Am6 is the first inversion of F#m7b5, also known as F# half-diminished, of F#o7 where the 'o' has a slash in it that I can't duplicate on the keyboard (too lazy).

 

Some people might find Am6 easier to read, as it has fewer printed characters. F#m7b5 seems better to me, especially if it leads to a B-based chord (circle of fifths).

[Analogaddict]

Yeah, and I would probably voice and embellish them differently. I might alternate a F#m7b5 with a B7b9, while I might play a D9 instead of an Am6. If what you are playing sounds good in the context, you've got it right!

[Dave Horne]

Since most chords are constructed in thirds that Am6 might be looked at as an F#ø7 (or F#m7b5) ... or F#ø7/A. (F#, A, C, E)

 

There are occasions where it really makes more sense to write Am6. Imagine a tune where the chord changes are Am, Am+, Am6, Am7, AmMajor7. This would be an example where we would probably write Am6 instead of F#ø7/A.

 

When I grew up in the 50's and 60's most sheet music had a minor chord with an added 6th and it was later when we saw half diminished 7th chords. Sometimes it's easier or it makes more sense to write it one way than the other.

[B.T.]

Thanks for the education guys. The chord does lead next on to a B7 chord. I'm a little rusty with theory and when looking in a chord book that had the F#m7b5 and the Am6 and each of their 3 inversions none of the eight had the exact "line-up" of the notes that I saw on the sheet music--which were F# in the bass clef and from bottom to top the C,E,A notes in the treble clef.