The slash chords (a.k.a. split chords) are named so because of the slash symbol in the chord name. For example C/D is a C chord with a D as the bass note. Therefore, it includes the notes D, C, E and G as opposed to a regular C chord including C, E and G.
The slash chords are related to inverted chords, but can also have a bass note that doesn’t belong to the original chord.
Let’s say you’re playing in a band; in this case you will probably stick to the ordinary C chord as the bassist will take care of the bass note D. But playing on your own you will instead include all the four notes on your guitar. It isn’t strictly necessary in the way that your music will be completely awkward just playing the regular C chord, but you will discover that there’re many possibilities to elaborate a song with slash chords (see suggestions of progressions further below).
Overview of slash chords
Slash chords sorted by note
The pictures above show some of the most useful chords with alternative bass notes. But there is more, and some are listed here in annotated form:
C/F: XX3010 / 1X201X
D/C#: X40232 / X4423X
E/D (E7/D): XX0100
Em/C (Cmaj7): X32000
F/G: 3X321X / 3X3221
See also: power chords with alternative bass note.
When the instrument sets the limit
It is possible to play all combinations in the area of chords with alternative bass notes. However, in some cases it doesn't work very well because of the instrument. In some cases, other better possibilities can be found by using alternate tunings.
Chord progressions with slash chord
Slash chords are often used to make smooth progressions between chords. Instead of change directly from a C to an Am the slash chord C/B can be put in between. This works well because the note B is flanked by A and C in the relevant musical scale. Here follows examples of the usability of slash chords in progressions:
C – C/B – Am
Another approach on the same theme is to insert a G/F# chord between G and Em. F# (F sharp) is positioned between G and E in the scale of G major.
G – G/F# – Em
A third example show a way to alternate the E - A progression:
E – E/D# – A
The following progression creates a descending bass line (Am/G can be easier to play as Am7/G: 302010):
Am – Am/G – D/F#
A slight nuance can be created by Em/D placed between Em and Cmaj7:
Em – Em/D – Cmaj7
Without being very common F/E could be used as an in-between chord by the same principles as the sequences above. (Instead for F - F/E it is also possible and quite easier to play Fmaj7 - Fma7/E.)
F – F/E – Dm
In the key of D, for example, a Bm to Bm/A sequence can be used as a bass walk (Bm/A can be played as X04432 or X0443X, the former is probably best in this case):
D – Bm – Bm/A – G
Chord progressions with many slash chords
In the same fashion as some of the examples above, but using two slash chords is also an alternative in some occasions. Scroll up to see diagrams.
The slash chord D/C# can be played by baring the three lowest string with one finger to be able to reach up to the C# on the fourth fret on the fifth string.
D – D/C# – Bm – Bm/A – G
Am – Am/G – Am/F# – F
This is a nice sequence and you can to play to strum the chords or just the bass strings in the Am/G, Am/F# movement, or something in between. The following two progressions have many similarities:
A – A/G – A/F# – E
E – A/F# – A/G# – A
For the above sequence you need to play the A chord with only the index fingers or use the thumb for the bass strings.
D – D/C – D/B – D/A
Dm – Dm/C – Dm/B – Dm/A
The similarities with the two progressions above are obvious. Both will sound nice, and especially with different finger picking patterns.
A similar example:
D – D/C# – D/B
Em/B – Em/D – C
E – E/B – E/C – E/C#
Two sequences with E minor and major respectively. Yes, it is true that C cannot be found in the E major scale, but it will still work as a chromatic bass walk.
Bm7 – Bm7/F# – Em
Another progression, why stop? This includes a minor seventh, and of course, you could elaborate almost endlessly with alternative bass note in several chord categories.
G – G/F# – C/E – Am/E – Am/F# – G
The progression above includes both slash chords in forms of inverted triads and with alternative bass notes. They create ascending and descending bass lines.
Although, it is not always that shifting to another chord via a slash chord works that well. Sometimes there are no perfect changes. Like C/D#, which on piano had been suitable between C and D, but there is no chord shape on the guitar that makes the transition smooth, and the bigger the changes are in finger positions, the less likely for the progression to sound great.
Famous songs with many slash chords
For example, is the Eagles song "Hotel California" consisting of a longer sequence with this chord type:
Am/C – E/B – G/B – D/A – F/A – C/G – Dm/A – E/G# ("Hotel California" by Eagles)
It's not unusual that slash chords, especially with four notes or more, coincide with extended chords. For example, Cmaj7/D and Fmaj7/G can be played with the same shape as D13sus and G13sus, respectively.
Dm7/G = G11
D/B = Bm7
A last comment
If you’re playing in a band; in this case you probably will stick to the ordinary chord as the bassist will take care of the bass note. But when playing on your own you will play all the four notes on your guitar. It isn’t strictly necessary in the way that your music will be completely awkward just playing the regular C chord, but as you probably discovered by now there’re many possibilities to elaborate a progression/song with slash chords.