Here is an overview of the chords to the solo section of "Foam" by Phish. They are listed below. Please note that each letter is a different chord and represents a distinct sound. Each letter lasts about a measure.
The “x/x” means that the primary chord is to the left, while the letter to the right is played in the bass note (meaning that note becomes a dominant part of that chord's sound). Unless otherwise noted, the bass note for the other letters is the same as the chord (i.e. the C chord starts with a C).
C - A/C# - G/D - Eb#5 - C/E -
F - D/F# - G - E/G# - Am -
Bbmaj7 - Am - Ab - C - D/F# - F - G (repeat)
Notice the bass notes. (You may need to get used to reading the letters as chords (and that the bass notes are on the right of the "/".) They go step by step up and then down (C-C#-D-Eb-and so on). So even though the chords differ greatly they are unified by the clear movement of the bass notes.
Take the first 2 chords as an example. The C chord sounds totally different than an A chord. They use different notes and have a different feel. But the song minimizes the disruption caused by this stark juxtaposition by linking the bass notes between 2 chords (C to C#).
So rather than focus on the change, we hear the chromatic lift from C to C#. This gives our ear an easy line to follow while provinding a rich sonic field of complex harmonies. It sounds simpler than it is, making the 2nd, 3rd, or 12th listening even more enjoyable.
The band uses these connections and complex harmonies to create melodic lines that work within (or work against) these links between chords. In jazz, these are called “passing notes” and are the key elements of soloing. Very simple in theory, but hard to master in practice.