music theory for musicians and normal people by toby w. rush Borrowed Chords how does a composer decide which altered notes to use? in a major key, altered chords use notes outside one possibility is using notes and chords the scale as a means of adding a from the parallel minor. different “color” to the chord. for example, the following chords are diatonic chords in c minor: w “borrowed”? b w w why call them b w w w w nw that when major & b w w w w w never brings w w7 w 7 them back? c: ii° ii° III iv VI vii° but if we use them in a major key, they require and are hey, minor! accidentals I’ll have them therefore altered chords. we call these borrowed chords because they back by tuesday are from the this time, I borrowed parallel minor. promise! bw w w bw w & bw bw bbw bw b w Nw some theorists C: wii° ii°w7 III iv VI vii°7 refer to the use b b of these chords as mode mixture. two of these chords, and, in fact, these six chords the “flat three” and “flat six,” are the six most commonly used have altered tones as roots. we place a full-sized flat symbol borrowed chords in the common before the roman numeral itself practice period. (One of them, the to indicate this altered root. major triad on the lowered mediant, or “flat three,” was not used much by composers before wait... since we the romantic era.) why? double the root, ˙ ˙ moving both roots & b˙ ˙ all the usual part-writing rules apply to these the same direction 5 chords. for example: can often result in parallel octaves. ? b˙ 8 ˙ b˙ ˙ VI V the borrowed supertonic is a b 6 diminished triad, and is therefore ˙ ˙ it’s more important to ii° always used in first inversion. & b˙ ˙ avoid parallelism than to resolve the notes a certain way, so this ? b˙ ˙ use of contrary the borrowed seventh chords 7 b˙ motion is better. can be used in any inversion, but the ˙ ii° VI V seventh must be approached 7 b and resolved properly. vii° the picardy third is a major tonic chord at the end of a minor piece, so many theorists consider it a borrowed it’s usually best to resolve altered chord. really, though, it’s not adding notes in the direction of their III chromatic variety... it’s a last-minute alteration, but doing so in the two b modulation! altered root chords won’t work. U VI œ #œ w bb œ œ œ œ b named for & ˙œœ#œ œ œ œ œ œ œ œ w the leading-tone fully diminished 24th-century seventh is the king of dominant explorer j j U 7 œ œ‰ œ ‰ œ œ œ n w function. don’t even think of jean-luc ? b œ œ œ œ œ œ picard!* b œ w resolving it to anything but tonic! vii° 7 6 g: i V i VI ii° V I *Nope. licensed under a creative commons BY-NC-ND license - visit tobyrush.com for more.