Re: Parenthesized second key signature

[Tyler Mitchell]

On Fri, Nov 30, 2018 at 06:14:20PM +1100, Andrew Bernard wrote:
> HI Mark,
> 
> Yes I note in both examples the key sigs are a semitone apart. Is this some
> convention in some church music? OP, help us out. I don't even know what to
> google for!
> 
> Andrew

Yes, Mark and David have it right -- it's more or less a 'hint' to
the accompanist that the piece can be played in either key. I say
'hint' because this is true whether the parenthetical key signature
is printed or not.

In my personal experience, I have only seen this in chant
accompaniments, though others here have mentioned other
possibilities.

I've often thought that the idea is to make it easier for the
singer (lower pitch) and/or the accompanist (fewer sharps or
flats), but sometimes it does neither (eg Bb Maj -> B Maj). I
suppose for some singers, higher is actually better.

The second example I gave is from here (in case you want to see
more):

http://www.ccwatershed.org/blog/2013/mar/19/1947-bragers-graduale-organ/

I don't know what the 'rules' are for when it's printed or not;
there are a number of chant accompaniments with an Eb Major key
signature which seem playable in E Major, but there was no
secondary key signature given.

(* And yes, I know chant isn't in, eg, "E Major", I'm just writing
it this way for the sake of simplicity.)

Cheers
Tyler