How to choose a key?

[kayordee]

I'm curious about how a composer chooses a key for a song. What qualities make each key different? Why choose D minor over C# minor? Why was beethovens 5th in C minor or why was Rachmaninovs 3rd piano concerto in D minor? I want to know what people think or if there is some form of reasoning behind key choice. Thanks for your replies

[kayordee]

Does anyone on this forum know what the concept of tonality is? I guess not

[gyzzzmo]

Does anyone on this forum know what the concept of tonality is? I guess not

You are indeed right, there is not a single soul on this forum who has even heard of it. Actually, we are all musical barbarians and only enjoy very, very loud 'songs'.

Gyzzzmo

PS. Even worse: We have a fellow playing the banjo here.

[ted]

Unsophisticated as we are, there is probably some interest in answers from those of us who do compose or improvise music based on keys, conventional or otherwise. I doubt that a general answer could be found but I might be wrong. I can only answer conclusively for myself. A quick trip through my old compositions turns up examples in nearly all keys, with a slight preference for four to six sharps or flats in both major and minor. I haven't the slightest idea why. My improvisation is usually a massive poultice of sections in all keys, none of which last for very long. I do notice a disconcerting number of Db major conclusions though. Again, I don't know why.

As all my music is conceived at the instrument I think it probably just depends where I happen to start, and that could be anywhere.

 

[brogers70]

I don't know, but some reasons for key choice might be

1. Prior to even temperament individual keys had different characters
2. In vocal music, where in the range of the most important voice you want the tonic or dominant to lie
3. In instrumental music some keys are easier than others for specific instruments (2-4 sharps for guitar, 3-5 sharps or flats for piano)
4. If the composer has perfect pitch different keys may feel different
5. Different keys may become conventionally associated with different moods, for a single composer or in a particular era and country
6. Composers may have sentimental attachments to keys for private reasons (whenever I play something in Eb major I just can't stop thinking about her...)

[Bob]

For the color.  Whatever they hear as the color.

For the color of the instrument in that range since it's in a certain key.


For practical reasons - For orchestral music, strings like sharp keys over flat keys. 

[kayordee]

Nice responses  . I like to imagine keys in different colours. I like to think that pieces are in certain keys because if the piece were to be played in a significantly higher or lower key, some parts sound different because of the tone of that range of the piano.

[timothy42b]

For practical reasons - For orchestral music, strings like sharp keys over flat keys. 

This is my approach.  Well, I don't really "compose," but I do arrange for various groups.

I choose a key that will be easiest for amateurs on that particular instrument to play.  If I have amateur guitars, I am not going to write in Eb, I'll use D.  With brass, I'll stay away from too many sharps.  With singers, I make sure it doesn't go to high or low for the average.

Occasionally I mess up.  I wrote Doxology parts for a brass group in G to match the piano at a Christmas service.  The amateur brass players I had that day were thrown off and they crashed and burned, though they did okay on the carols I'd given them (carefully written in Bb, mid range).

[Bob]

G wouldn't be too bad.  A for Bbs.  G for low brass.  D for the horn.

[liordavid]

I think that it was just the inspiration when he started writing the piece