pair C major with is its dominant seventh chord , G7 ( G-B-D-F ). Remembering that every key has a similar correlating tonic / dominant seventh pair ( F-C7 , G-D7 , Bb-F7 , etc .) should put these very familiar two chord patterns into a simple to understand musical perspective .
Brace yourself … the FINAL new concept is here . In the key of C , chords such as D7 , A7 , E7 , etc . are called Secondary Dominant chords because they use a note that is not part of the C scale to add interest or lead the listener ’ s ear to the next chord . For example , in the key of C , D7 ( D-F # -A-C ) is a secondary dominant chord because it uses an F # ( instead of F natural ) as its third . Likewise , A7 ( A-C # -E-G ) is a secondary dominant because it uses C # ( not C natural ) as its third . To keep things simple , note that most secondary dominant chords share a root and fifth with their correlating diatonic chords in the harmonized scale . This means that they are still quite close to their harmonic environment , but there exists one note which adds “ spice ” to a chord progression whenever you use a secondary dominant .
Okay , how are secondary dominant chords used ?
Due to the common root note in many cases you can replace a diatonic chord with a secondary dominant . Here ’ s an example of a simple chord progression :
C – Amin – Dmin – G7 ( all diatonic chords )
Which can turn into :
C – A7 – D7 – G7 ( replacing Amin and Dmin with A7 and D7 ), or C – A7 – Dmin – G7 ( replacing only Amin with A7 ), or C – Amin – D7 – G7 ( replacing only Dmin with D7 )
How and when these chord substitutions are made is determined by both the melody of a song ( which might result in musical clashes with particular chord substitutions ) or by how your ear hears the most effective chord progression . So long as the chords you select support and do not clash with the melody , there is no such thing as a “ wrong ” chord progression for any given song . Yes , we may be comfortable with the simple chords we ’ ve played and heard for years , but it is those players who musically expand upon those basics which , as I mentioned before , stand out because of their re-harmonization of even the simplest of songs .
Okay , I promised a simple example to put much of the above into context . Below is the first strain of Oh Susanna in its simplest form … note the use of only the root and dominant seventh chord :
20 ALL FRETS SEPTEMBER / OCTOBER 2020