Slash chords are often considered mysterious and hard to work with by because it is not always clear what sort of chord they are, and what to play over them. In this lesson I am going to demystify slash chords a bit and I will go through all Major Triads over bass notes to help you get used to interpreting this type of chord.
What are slash chords
The slash chord is a very common device in music with chords that have extensions. Most often it is used to describe a sound that the composer or arranger want at that point in the song. It is also mostly the case that the slash chord D/C will be a D major triad over a C bass note. In some cases you can have a D major triad over a C major triad, but usually that is then added information in the score.
Since we are used to interpreting chords by their basic 7th chord type: m7, dom7, dim etc. It is confusing and unclear to suddenly be presented with a chord that is the combination of a triad and a bass note. But as I will try to demonstrate in this lesson you can interpret the notes of the triad against the bass note root and get an understanding of the chord that will put it into one of the more basic categories for chords that you probably already know. It takes a bit of investigation because the chords are often not complete (ie with a 3rd and a 7th).
I am assuming that you are able to oversee the notes of each of the major triads and will not name all the notes all the time in the video but instead just describe what they are related to the C root that I am using through out. In exampl 1 Ihave written out one way to play the Bb/C voicing. If we let C be the root of the chord then the Bb triad would be: Bb(b7th), D(9th), F(sus4 or 11). So we have a C chord with a b7, a sus 4 and a 9: C7sus4(9).
12 major triads over a C bass note
The idea of example 2 is quite simple even if it is a lot of material. I have taken a C as a root and then I am moving a triad chromatically from C to C and looking at what kind of chord it gives us.
In my experience the most common use of slash chrods is a major triads over a bass note, sometimes there will be another upperstructure like a 7th chord or a minor triad, but the approach to figuring it out is then the same as what I am doing here.
The first example is a C triad over C which is of course still a C major triad.
B/C: B major triad is B(maj7), D#(m3) and F#(b5). You’ll notice that you have to think of D# as an Eb to realize that is is a m3. The combination of a m3 and b5 tells us that it is a diminished or half diminished sound, and the fact that it has a maj7 makes it clear that it is not a half diminished.
Bb/C, The third chord is what I covered in example 1: C7sus4 .
A/C is an interesting and very useful sound. If we look at the extensions it gives us: A(13) C#(b9) and E(maj3rd) so we have a major chord with a b9 and a 13. This is most likely a dom7th chord, there are not that many scales with a maj7, root and b9 but there are 2 quite common ones with a 13b9 on the dominant. The most used of the two being the diminished scale.
Ab/C is quite trivial since C is the 3rd of Ab making it a first inversion Ab triad.
G/C spells out: G(5), B(maj7), D(9th) so we have a maj7th chord with a 9th. In most cases this is going to imply a major 3rd so that you can use it as a Cmaj7(9) chord, and as I show in the video it is a maj7th voicing that I use very often.
Gb/C: Gb7 is of course the tritone substitute of C7, which might already hint at what sort of chord this is. If we look at the notes: Gb(b5), Bb(b7th), Db(b9). With all these alterations this chord is most likely to be used as an altered dominant, but you could also think of it as a chord out of the diminished scale.
F/C is again an example where C is part of the F major triad so it sounds like a 2nd inversion F major triad.
E/C is a very useful way to play a Cmaj7(#5) When we look the notes it’s quite straight forward: E(maj3rd), G#(#5) and B(maj7)
Eb/C is (as might even be obvious from the voicing) a Cm7: Eb(m3) G(5th) Bb(b7th) .
C/D the last two examples are a little bit more ambigous, especially this one: D(9th), F#(#11), A(13th) This chord is used both as a Cmaj7th(#11) and a C7(9#11) so it can be a dominant or a maj7th chord, and you have to figure it out from the context what works better when you solo on it. If the one comping is just playing this voicing both should work, but often one will be more logical in the song than the other.
Db/C is a phrygian sounding chord, Db(b9), F(sus4 or 11th), Ab(b13). So we ahve some sort of sus4b9 sound which is mostly interpreted as a phrygian sound though you could use other scales over it.
So that was all the slash chord combinations of a major triad over a bass note.
Using some slash chord voicings
In the examples I have chosen to not write the slash chord but instead the interpretation of the chord because that makes it clear how it functions in the progression.
The first example is a II V I cadence in the key of F major. The first chord is a Gm7(11) and the slash chord voicing in this example is an A/C which is a dom7th chord from the diminished scale that resolves to an F6/9 chord.
The 2nd example is demonstrating using the D/C as a tonic lydian chord (if that makes any real sense). The progression is a II V I in the key of C major.
The final example is using the Gb/C voicing, so that is the dominant of a II V I in the key of F major. As I mentioned you could interpret this voicing as coming from the altered scale but also the diminished scale.
I hope you can use the information I went over here to get more comfortable with slash chords and maybe start to add them into your own playing and writing. A lot of interesting voicings can be made with these and often part of what works well with them is that they are incomplete and therefore slightly surprising to the ear.
If you are interested in making a lesson on what voicings you can make if you start using the bass note not as a bass but as a part of the chord, since this can yield some interesting voicings, probably also because the sounds are incomplete.
If you want to download the examples from this lesson as a PDF you can do so here:
If you have any questions, comments or suggestions for topics or how I can make the lessons better then please feel free to leave on the video or send me an e-mail. That is the best way for me to improve my lessons and make thme fit what you want to hear.