My old standby chart of generic bass lines using the major scale box as a Rosetta stone may help:
Bass Patterns based upon the Major Scale box.
Major Scale Box.
G|---2---|-------|---3---|---4---| 1st string
D|---6---|-------|---7---|---8---|
A|---3---|---4---|-------|---5---|
E|-------|---R---|-------|---2---|4th string
Cmaj7 chord coming up in the song. Whoa, right there, where will I be seeing this Cmaj7 chord? Answer; In the fake chord sheet music the band director hands to you.
http://tabs.ultimate-guitar.com/m/misc_traditional/home_on_the_range_crd.htm
OK back to that Cmaj7 chord. Find a C note on your 3rd or 4th string and put the box's R over that note, then use the chord's spelling for the bass line, i.e. Cmaj7 has a spelling of R-3-5-7. Normally we start pounding out roots only, and then add 5's as we get comfortable, an 8 or octave note fits nicely R-5-8-5. As you need more notes in your bass line grab the correct 3 and 7. Ed Friedland's book
Building Walking Bass Lines has the rest of this story. The spellings you need are listed below.
Review; See the chord, visualize your major scale box pattern, place the R (root) note of the box's pattern over that C note on your fretboard and then play the spelling of the chord, in this case it will be the R-3-5-7. You will need a fretboard chart showing the notes on the fretboard. I've dropped one in several of the posts I put here.
Basic Chords aka the triad.
• Major Triad = R-3-5
• Minor Triad = R-b3-5
• Diminished Chord = R-b3-b5
7th Chords We will probably be playing in 4/4 time. Four quarter notes per measure - the 7th chords have four notes in their spelling, thus fill out a measure very well.
• Maj7 = R-3-5-7
• Minor 7 = R-b3-5-b7
• Dominant 7 = R-3-5-b7
• ½ diminished = R-b3-b5-b7
• Full diminished = R-b3-b5-bb7
See a chord and play it's chord tones. As every key will have three major, three minor and one diminished chord it's a good idea to get your major, minor and diminished bass line chord tones into muscle memory so when you see a chord your fingers just know what will work. Now the song may only give you enough room for the root, or root five - adapt and get as many chord tones into your bass line as needed. Root on 1 and a steady groove from the other chord tones plus something to call attention to the chord change is what we do.
Generic Notes - for your bass line.
• The root, five and eight are generic and fit most any chord. Remember the diminished has a flatted 5.
• The 3 is generic to all major chords. So R-3-5-3 will fit under any major chord.
• The b3 is generic to all minor chords. And R-b3-5-8 will fit under any minor chord. Why the 8? Well the 8 is just another root in the next octave.
• The 7 is generic to all maj7 chords. Yep, R-3-5-7 fits nicely.
• The b7 is generic to all dominant seventh and minor seventh chords. G7 = R-3-5-b7 or Gm7 = R-b3-5-b7.
• The 6 is neutral and adds color, help yourself to 6’s. Love the sound of R-3-5-6 with a major chord.
• The 2 and 4 make good passing notes. Don’t linger on them or stop on them, keep them passing.
• In making your bass line help yourself to those notes, just use them correctly.
• Roots, fives, eights and the correct 3 & 7 will play a lot of bass.
Scales -- We gotta do our scales so our fingers know where to go, however, chord tones not scales is what we play 90% of the time. Here are some spelling for several of the scales - get the Major Scale into muscle memory first and then I've listed some of the other scales so you will not get bored.
• Major Scale = R-2-3-4-5-6-7 Home base
• Major Pentatonic = R-2-3-5-6 Leave out the 4 & 7
• Natural Minor Scale = R-2-b3-4-5-b6-b7 Major scale with the 3, 6 & 7 flatted.
• Minor Pentatonic = R-b3-4-5-b7 Leave out the 2 & 6.
• Blues = R-b3-4-b5-5-b7 Minor pentatonic with the blue note b5 added.
• Harmonic Minor Scale = R-2-b3-4-5-b6-7 Natural minor with a natural 7.
• Melodic Minor Scale = R-2-b3-4-5-6-7 Major scale with a b3.
Let the major scale be your home base then change a few notes and you have something different. No need to memorize a zillion patterns. Let the major scale pattern be your go to pattern - then adapt/adjust from there.
