Absolute Theory Beginner

[JoshJ]

I started learning guitar when I was about 10, had lessons for a couple of years and got to what I would consider a good standard (for a 12/13 year old). I could figure out (a simplified version of) most songs fairly quickly, but I never bothered with any theory whatsoever so I was always useless at improvisation, and ended up getting bored with playing and trailed off over the last 7 years.

A few weeks ago I bought myself a double bass, 'cos I want to learn to slap and play psychobilly/rockabilly. I've already learned a lot more theory than I ever knew before, and I've been looking at [url="http://www.studybass.com/tools/chord-scale-note-printer/"]this gizmo[/url], hoping it will help "open up the fretboard". I've only used the chords on it for now, first I put in Dmin7 to see what scott devine was doing in his "how to practice arpeggios" tutorial, and now I'm getting to know my way around that I want to try some other chords.

It seems kind of pointless learning lots of different chords/arpeggios without knowing how to use them, so my annoying newbie question is:
"What are different types of chords for?"

Pretty much all I really know so far is:
major chords = happy
minor chords = sad
"Root-5th" sounds bluegrassy

If someone could extend this to include pentatonic, triads, dominant/diminished 7th/9th, etc. etc., that would be a massive help.

I'm not after a really in depth explanation, just simple guidelines to get me started, for example:
"If you want something to sound ____, use ____ and avoid ____."
"_____ is mostly used in rockabilly/jazz/blues/pop"

[Bilbo]

Its really not that simple, Josh. A major chord can sound sad and a minor one happy, depending on context (i.e the chords before it and the chords after it) and that's before you bring in the other variables such as rhythm, melody and dynamics. You need to learn about the relationship between chords and scales so you can join them all up. I am not going to produce a list here because it will be of limited use but Major Minor's boot camp stuff is worth a look as is Mark Levine's Jazz Theory book. Find a musician who understands theory and get them to explain soem of the basic stuff. and take it from there (isn't Out To Play Jazz over your way?)

[JoshJ]

[quote name='Bilbo' post='985816' date='Oct 12 2010, 03:21 PM']Its really not that simple, Josh.[/quote]
Hmm, I suspected as much... I don't know really what I was hoping for; once happy and sad are gone I guess the emotions would get a bit abstract.. "Pentatonic = perplexed, Diminished 7th = optimistic, dominant 7th = surprised..."

Thanks for the reply, anyway. I suppose I will just have to learn the hard way!