@ColinThomson said:
Don't tell me everyone here thinks that all keys are exactly the same, and the only reason to choose one above another is what the singing voice can do, or what individual instruments can do. There must be more than that.
[H]
Congratulation, you got it. In twelve-tone equal temperament all keys are equal!
In todays music where the equal temperament is in use, all keys are equal, or in other words, they can only be darker or brigther by range, pitch, instrumentation etc., but not different in timbre by having in each key different interval proportions.
In the times of Johann Sebastian Bach, that was not the case. With the temperament he was using, each key had another timbre, and was used accordingly. When you play Bach’s composition on a keyboard tuned to the tempreament he composed with, you can hear the dramatic’s when modulating to the most far away keys from the pure center key the instrument is tuned to, and certainly he made use of that in absolute perfectionism. There are sad keys, joyful keys, keys for the Lord, keys for requiems, keys for blondes and brunettes etc. etc..
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