J.P.-
I would never suggest someone start out with this system first. The first systematic approach to chords on the regular guitar that I worked with was to think in terms of five positions, and then just memorize things in relation to the major chord forms in each of the five positions. I agree that the way to understand how chords are formed should be based on altering the major chord. The diminished concept IS putting the cart before the horse in terms of the theoretical forming of chords.
What the diminished concept should be seen as is simply a mechanical way of quickly creating physical chord shapes, that works great on the regular guitar, and if Bengt is onto something, may have some potential on PSG also, although my 3+4 setup doesn't have all the changes Bengt is using.
I know you play regular guitar too, J.P., so let me see if I can better describe the purely mechanical benefits of the dim. concept on that instrument.
First, let's say we want to deal with five basic string groups: 6-5-4-3, 6-4-3-2, 5-4-3-2, 5-3-2-1, and 4-3-2-1. As far as pure four-note chords, this takes care of all the common string groups. What the dim. concept offers is a way to quickly (once you grasp it) create chord forms for all four inversions of any of the basic four-note chords, on all of the mentioned string groups. Once you derive the chord forms you want, then you can use them on their own, without having to refer to a particular dim.7th chord. The diminished concept isn't something that someone should have to worry about while they're actually playing. It's just a way to create physical chord shapes that frees a person from having to refer to a chord book or have a great memory. If I want to play a little jazz progression in a certain position, I'll use it to find quickly reachable chords in that position. Or, since it shows you all inversions of a chord on a particular string group, it gives you four different inversions to go up and down between on that string group, that sound perfectly related to each other. I think if we were sitting together with a couple of guitars, I could show you ways of playing through all four inversions in a way that would allow you to appreciate the way these inversions sound perfectly related to each other.
I'm sure that if somebody wanted too, they could sit down and figure out these same mathematically pure four-note inversions some other way, but for me the diminished concept (and the augmented concept mentioned above) are just quick "slide rule" tools to accomplish the same thing, almost instantly. It works just as quickly as taking any pure four-note dim.7th form and playing it up and down the neck in three fret jumps, something I bet you've done. It does take a bit to get the hang of, but to me it's well worth it. After I get a four-note chord, then I can follow certain other principles to create forms for more exotic chords from the basic four-noters.
So far, I've been talking about deriving chords by moving one shape up the neck horizontally to get four different inversions for the same letter-named chord.
Bengt descibes the other way to apply the dim. concept, which is to stay in one position and drop each note in the dim. form one at a time, to create forms for four DIFFERENT letter-named chords. He alludes to the idea that altering a single dim. form four ways on three adjacent frets will give us one inversion for all twelve letter-named four-note chords of any type. That's EXACTLY it.
So, it can be used one of two ways; either find four inversions for the same letter-named chord moving up the neck horizontally, or by taking a single diminished chord form and moving it one fret, and then another, creating at each of the three frets four different letter-named chords, one can get a chord for each of the twelve letter-names.
Bengt, I'm not sure about what you were saying in the first part of your last post, but it works best for me to drop a note to create a dom. 7th first, and then proceed to alter from that same root to get maj.7, min.7, and m7b5.
J.P.- I know this whole thing seems screwy from the outside, but if you messed with it a bit you might find something you like. In another thread you spoke about using dim. and aug. chords as passing chords a lot, so I'll bet you have a real strong foundation in their use already. I wouldn't mind hearing about some of those uses sometime. If you're at all interested in these ideas and want me to clear them up a little, E-mail me. Maybe I could ask you about the passing chord usage at the same time. Or, if the above seems totally irrelevant and unnecessary to where you're at, that's fine. I totally understand.
Now ,friends, I'm going to sign off before I get a headache! Have a great weekend.
Jeff S.
<FONT SIZE=1 COLOR="#8e236b"><p align=CENTER>[This message was edited by Jeff A. Smith on 13 April 2001 at 06:02 PM.]</p></FONT>