Neil,

You are correct, I think. When I need to form an unfamiliar chord, I form one from which the target chord may be derrived and see what I have to change. Of course you can't do that unless you already know how the target chord is constructed musically. Not only that but you must also know where the root, third, fifth, sixth, seventh, etc. are in each chord pattern you play so you know which fingers to adjust. I do this when trying to work out a new piece. If I'm in a jam session or playing from a lead sheet, I need to play a sutible substitute that I already know even if the voicing isn't what I'd prefer.

As for roots, you are also correct. The root of a chord is the note from which the chord derrives its name, i.e., the tonic note. In the key of C the root of the G7 chord is G, not C.

There are situations with double sharps but I don't recall seeing a piece written in D#. I know quite a few tunes that are in Eb. I view the double sharp as a copout so we can pretend that a D# scale doesn't really have two Gs and no F. But then I'm not properly trained in music.

The music I play most of the time (Bluegrass, old-timey, country blues and other assorted traditional stuff) doesn't call for very elaborate chords. Well, blues has a lot of sevenths and ninths but those aren't exactly exotic. It's jazz, which I also enjoy, that provides real fun when it comes to chords. There you need to have a system of chords that lets you control the bass line, keep successive chords in the progression as close as possible, and still lets you add and substitute easily. First position chords or any chords with open strings really aren't very useful here.

You're in Des Moine(s)? I'm over in Cedar Rapids and I get to Des Moines on occasion. Do you have jam sessions over there?

Cheers,

- Mark