Walk on The Wild Side
Let's start simple: two notes at once. A great example from the classic rock world is Lou Reed's "Walk on The Wild Side". The studio version was actually cut with two basses. Herbie Flowers played the low part, sliding from C to F and back on an upright bass. He then switched to bass guitar and overdubbed an E over the Cs, making a C major chord, and an A and a C over the Fs, making an F major chord.
Does your band have two bass players? Neither does mine, so to play it live, use the 8th fret of your E string for the low C. You'll probably do best using the left-hand index finger to fret this note. At the same time, use either the middle or ring finger to grab the E on the G string's 9th fret. Once the left hand is comfortable, try using either the index and middle finger, or the thumb and index finger, on the right hand to hit the E and G strings simultaneously.
When you've got that working, try hitting those notes again and sliding your left hand five frets towards the body of the bass, so you end up on the E string's 13th fret, and the G string's 14th fret. Hit those notes that you've slid into again, and slide back to where you started. That's it! For the most authentic replication of the original, replace the G string's 14 fret note with the 17th when you're hitting the notes again to slide back. You'll likely need the little finger on your left hand for that one.
My Friend of Misery
Now let's look at some minor chords; Metallica's "My Friend of Misery" has a really cool bass intro going back and forth between D minor and A minor chords. The voice leading is “oblique,” which means some of the notes move and some don't. A D minor chord consists of D, F and A, and an A minor chord consists of an A, C and E. Jason Newsted used the open A string for the A in both chords, so only two of the three notes in the chord actually move.
For the D minor, Jason started with the open A string, which is the 5th of the chord, added D, or the root of the chord, on the 12th fret of the D string, and F, the 3rd of the chord, on the 10th fret of the G string. For the A minor, he kept the open A, the root of this chord, and moved the fretted notes to the 10th fret of the D string, which is C, or the 3rd of the chord, and the 9th fret of the G string, which is E, or the 5th of the chord. Practice going back and forth between these two chords, and when you're ready, try out the complete bass part.
The songs spend two measures at a time on each chord. The first measure uses the voicing we've already learned. The second measure adds a higher incidence of the 5th of the chord in the D minor section, which is an A on the 14th fret of the G string in this instance, and a 7th in the A minor section, which is a G on the 12th fret of the G string. Then you can walk through a scale note to get back to the beginning. The right hand can use the index finger for all A string notes, middle finger for all D string notes, and the ring finger for all the G string notes.
To hear some more chordal bass playing check out Flea on the Red Hot Chili Peppers’ “By the Way” or “Soul to Squeeze”, Rammstein's Oliver Riedel on "Seemann;” Jeff Berlin on "Tears In Heaven” and "Dixie;” Geddy Lee of Rush on "Force Ten”, and Henrik Linder from Dirty Loops on "Baby”, to name a few. You can always find some inspiration for chordal bass playing in the songs of your favorite artists!