#1
Whenever i try and right music it always comes out as dark and sad for some reason. What's the difference between major and minor keys? as in how is a minor key different from it's realitive major.
#2
the technical difference is 1 half step, but its true that minor can seem darker, but if you try harmonics in the vocals compared the the actual music you may find a positive outlook on the song, i do at least XD
#3
Minor scales have different scale degrees and intervals and effectively resolve on a different note.

Songs will naturally want to resolve on the note that means major so you'll have to force the song to resolve to the note that means minor. This is usually done by accidentals (especially a raised seventh in natural minor scales). Minor scales are pretty complex so you might want to get major scales completely down.
Nothing wrong with major scales btw, they're just as capable of doing sad songs as minor scales, you're writing sad music because you're going through a depressive phase in your life.
#5
Quote by Aurex
the technical difference is 1 half step, but its true that minor can seem darker, but if you try harmonics in the vocals compared the the actual music you may find a positive outlook on the song, i do at least XD

no, he means the difference between like E minor and its relative major, being G major.

too answer your question, its basically the structure of the song, which chords you use in the key, and how you vocalize your lyrics.
but if you like your sad music (most of my music is dark), than by all means, keep writing!!
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