I think it "meant" an Am(maj7), it just went about it a weird way.
Normally the "+" means "augmented". So you might see a C+ or C+5 chord as an alternate way of saying Caug. To "augment" means to sharpen the note (raise it up one fret... also known as one half-step). So instead of playing the normal "5" note of the C chord, which is a G note, you'd augment it and make it a G# note.
But you wouldn't normally augment a 7th of a chord. If you sharpen the major 7th of a chord, you just wind up with the root of the chord an octave higher. And if you sharpen a minor 7th, you just end back up with a major 7th.
I get what the person was
trying to do. The 7th of a minor 7th chord is a minor 7th. So I guess it makes sense in some way to call it a "+7" if you wanted to sharpen it (augment it) back up to a major 7th. But then you'd just call it a major 7th and be done with it.
To call it a "+7" is kind of like calling it a "sharp flat 7" with is just kooky. Sort of along lines of me saying that I'm 5'15" tall instead of 6'3". I mean, it's technically the same height, but nobody says it that way!
JJ
