Originally Posted by: B_DylanOK, so I know my basic 5 scales. Major, Minor Pentatonic, Blues Scale, Major Pentatonic and Minor. I've been reading through some of the thread on the MB and I now know about chord formations in the major scale: Maj, Min, Min, Maj, Maj, Min, Dim. Does anybody know what the chord formations are in the other scales or is there a logical way to work them out. Also, when your trying to learn a song by ear, what do you listen for. Is it the first chord, for example G, to tell you what key your in, are you listening for the scale and how do you identify what scale your in if the key is G. Can anybody help?

Don`t assume that those are the only chords you can get from the major scale.
If you harmonize the scale with triads, then, yes you get the chords you mentioned.
And if you harmonize the scale with seventh chords you get:
Maj7, Min7, Min7, Maj7, Dominant7, Min7, dim7.
And the logical way of building chords is taking a note and then stacking thirds above that note.

Em Scale=[ E,F#,G,A,B,C,D,E]
Let`s make a chord on the fourth note(A)
You are gonna need the "A" as the root and then go every other note.
[A,C,E] and this is an A minor chord.

Another example?
Let`s make a chord on the third note(G)
Take "G" and then stack intervals of third above it(every other note)
{G,B,D} or a G major chord.

There you go buddy, that is the most basic way of making chords.