Relative key modulation - reasons for doing so?

[Westenra]

Was listening to the radio today and the classic 'Take Five' came on, after humming it for several hours later I decided to look at some sheet music and a breakdown of it. When reading one description it said the tonal centre shifts from Eb minor to Gb major then back again. 

What I don't get it is the reason for the relative major key modulation? If all the notes are the same then the only two things change which are the chord progression notes and the tonal centre, right? What other reasons would you have for switching to the relative major/minor key?

[leftybassman392]

1 hour ago, Westenra said:

Was listening to the radio today and the classic 'Take Five' came on, after humming it for several hours later I decided to look at some sheet music and a breakdown of it. When reading one description it said the tonal centre shifts from Eb minor to Gb major then back again. 

What I don't get it is the reason for the relative major key modulation? If all the notes are the same then the only two things change which are the chord progression notes and the tonal centre, right? What other reasons would you have for switching to the relative major/minor key?

Others will have more detailed responses to offer no doubt; but to state the obvious, one's a minor tonality and the other's a major tonality. The writer is looking to draw a distinction between the fairly dark character of the main theme and the somewhat brighter second theme. Yes it's all drawn from the same collection of notes, but it's to do with emotional impact.

[dlloyd]

You deal with a minor key differently to how you would deal with its relative major.

The notes would indeed be the same if you stuck to Eb Aeolian (natural minor) and Gb Ionian (major)... and if you were noodling about playing scales or random notes, it probably wouldn't make much difference. It would sound as crap in both instances.

It's a tune we used to do in my old band and I would tend to play in Eb Dorian and Eb harmonic minor with a smattering of Eb pentatonic minor when soloing on the minor part... I wouldn't do that on Gb major, but then you don't generally solo on that part of the progression...

[Westenra]

What sort of colour would using the dorian bring with its raised 6th?

[dlloyd]

It's a very common scale to use over a static minor progression. Think "So What" by Miles Davis. It's difficult to describe what effect it has, but it's bluesy and adds some warmth I suppose... It's like a step towards melodic minor without hammering out the v as a dominant chord. It sounds good.

No doubt someone will be along to explain why...

 

[Andrej]

I can't speak for somebody else, but in my case it depends on where I want to go out of scale to with the melody.

I sometimes go to "major" to add bits of lydian/aug 4th on the melody without actually changing the tonality. Alternating Aeolian/Dorian melodies over Aeolian is also pretty common, and it would involve altering the same note (Cb to C would be 4# on Gb, and Cb to C would be major 6th on Eb minor). There are many things you can do with that, and switching between relative major/minor scales is a simple way to do it because it's always easy to resolve. Works for me at least.

 

 

[Bagman]

On 5 December 2017 at 21:01, dlloyd said:

It's a very common scale to use over a static minor progression. Think "So What" by Miles Davis. It's difficult to describe what effect it has, but it's bluesy and adds some warmth I suppose... It's like a step towards melodic minor without hammering out the v as a dominant chord. It sounds good.

No doubt someone will be along to explain why...

 

I can speak only to myself but yes Dorian 'feels' blue

[FDC484950]

I would dispute that this has a relative major move - it’s a perfectly diatonic tune in Ebmin. If you listen to the original track there’s not one note outside Eb aeolian on the head, other than the flat 5th and the odd passing note to give it a vaguely bluesy sound. Also the solos are a one chord vamp on Ebm. For a true shift to a relative minor/major I would expect to see the root chord treated differently - for example an Eb min maj7 or Ebmin6 on the minor key, and maybe a Gbmaj7#11 on the major. Something that unmistakably identifies the key centre as being different - whether that be a chord someone plays, or a melody line that implies it.

[FDC484950]

On 04/12/2017 at 14:25, Westenra said:

What sort of colour would using the dorian bring with its raised 6th?

Actually the Dorian has a natural 6th. It gives a brighter sound and is far more commonly used over an indicated min7 chord on a jazz chart than the aeolian mode. If you hang on that 6th you’re effectively implying a min13 chord. You can then imply all 3 extensions by (for example on Cmin) playing D, F and A - this is a Dmin triad played over a Cmin chord but implies 9th (D), 11th (F) and 13th (A). Try it against a chord - it sounds interesting!