Borrowed Chords question in Songwriting?

[generatemusic]

When songwriting in a major key, it's common to "borrow chords" from the parallel minor key... such as the bIII & bVII chords, without modulating.

But how about if you are in the minor key? Does this practice still apply?
What are some "borrowed" chords that get used a lot? Any examples would be helpful.
Thanks

[Malcolm]

When writing a melody - in a major or minor key - what chords do you want under your melody? Think about that for a moment.

Ultimately you want the melody line and the chord line to share like notes. When you have both melody line and chord line sharing like notes the two lines harmonize and sound good together. If your melody line has moved on to notes not found in the old chord - or you insert a new chord that does not share like notes with the melody - you fall out of harmony, and need to find a chord that will harmonize this new melody -- or -- insert the needed harmonizing note into an existing chord, i.e. as an extension, augmenting or substitute a chord that now harmonizes the new melody. That to me takes center stage over any thing else. Now if you can get the melody taken care of and add some interest, flavor or color by substituting or moving from major to minor - help yourself, but, substituting for the sake of substituting may not accomplish harmonization. Sub all you like if it harmonizes.

Keeping harmonization in mind here are some acceptable chord substitutions....
ii and IV both being sub-dominants sub for each other.
v and viidim both being dominant sub for each other.
I recently read that iii, vi and I sub for each other - never used this myself.
Major to minor (same cord) as you mentioned happens.
b7ths are added seemingly with out rhyme or reason and 9's, 11's and 13's are added for color.

I'm sure there are other chords that sub for each other. Interested in seeing what others have to say.

[JonR]

When songwriting in a major key, it's common to "borrow chords" from the parallel minor key... such as the bIII & bVII chords, without modulating.

But how about if you are in the minor key? Does this practice still apply?
What are some "borrowed" chords that get used a lot? Any examples would be helpful.
Thanks

The minor key already borrows the V from major (or more strictly from harmonic minor, I guess).
A major IV chord and minor ii can often be used in a minor key, and would be considered as coming from parallel dorian or melodic minor.
It's also fairly common to use a bII7 chord (eg Bb7 in A minor) but this - at least in jazz - is regarded as a tritone substitute (for V), not a borrowing.
However, one could use a Bbmaj7 (resolving to Am) and regard it as borrowed from A phrygian.
Another common change is to use F7 in place of Fmaj7 (in A minor) - which again one could interpret as a phrygian bVI, but is probably better seen as either a tritone sub for V/V (in place of seconday dominant B7), or as just a bluesy variation on Fmaj7 (the Eb being the blues b5 of the key).