This is a guide that talks about creating a fingerstyle arrangement for Amazing Grace, in the style of John Fahey.
It intends to show how you can use the (1) melody to find the (2) chord progression which gives ideas for (3) scales to use and then allows for the creation of (4) fingerstyle arrangements & harmonies; as long as you can hum the melody, you can play fingerstyle arrangements for Amazing Grace in any key and anywhere on the fretboard.
Here are the steps of the process:
To start off, using the common key of C, here's the melody for Amazing Grace in open-position, on the top-2 strings.
Note: the MuseScore tablature may take a moment to load...
It won't be talked about in detail here, but over time you can train your ear to hear a chord progression for melodies; it's possible to do because pianists like Art Tatum could improvise, playing melodies he'd heard in his right-hand, while playing chords in his left-hand to match. The point in mentioning that is to protect that idea of how you can do this all from just the melody! How to do this by ear won't be theorized here, for now you'll have to take this chord progression on faith..
Knowing a bit about the modes of the major scale, you can tell that all the chords from the chord progression come from the C-major scale. This is the C-major scale here, with the note priority as:
The only chord that doesn't really fit within the 'universe' of C-major scale notes is the D7, which one can consider as a subtitution from another universe of a key-center-major-scale. Choosing notes that complement the bass-notes, usually the octave/root (1st) or chord tones (3rd, 5th, 7th) are used. This helps to add some detail for the bass-side.
For adding 'resolution' to the treble-side, it's needed to remember that, for a Fahey-esque arrangement of Amazing Grace, the treble-side will involve some fingerstyle picking! A common conundrum is trying to sort out which treble-side notes land as a 'pinch' (alongside the bass note) or as an 'alternating' note (between the bass notes). Locally in this blog, let's organize 3-possibilities for treble-note (rel. to bass-note) timing:
To hammer this point home, here are examples of each 'mode' of picking, done in different keys. To get a full grasp and maximize comfortability with these picking 'modes' it's a prudent idea (though not without its challenges!) to try and extend these exercises in the different keys in each mode; that way, in playing situations it's at least possible to pull-out as you play.
Finding the freedom to use those 3 styles of picking on any chord, on any treble-side, at any tempo, that would be the ideal.. for the notes that you need to find anyway. But even running through those exercises a few times, it can loosen up stiff fingers that haven't been used to one of those picking styles in a long time. These ways of rhythmically varying the treble-side notes give ways of adding more detail to the melody.
Here's an idea for a 'final' version of Amazing Grace, that uses the more detailed alternating bass, and tries to embellish the melody using the different modes of picking. It also plays around with getting into the specific/'localized' inner scales, as the chords change, as ways of finding notes. But everything comes originally from the melody of Amazing Grace, even finding those inner chords.
This guide aims to demonstrate how you can create a fingerstyle arrangement for Amazing Grace, starting only with the melody. Granted, coming up with the chord progression is a crucial 2nd step, but there are many resources about harmonizing notes in the major scale, and that can also be a blog idea for another time! After finding the chord progression, that sets-up knowing which notes to add onto the bass-side, which then can get complemented by their own respective root/octave or scale-tone alternating bass-notes. Then, the treble-side can get varied up with the 3-different 'modes' of picking the treble-side notes against the bass-notes. It's all like adding onion layers around the kernal of the melody.
PS: you can see how 'Fahey-esque' things can get when that 'mode 3' style picking gets done, with the pickup note. Here on this Christmas medley, Fahey uses it right from the start of the recording several times.