The question is a bit tricky. It is the key that defines the song’s tonal home. When you play a chord that embodies this tonal home, the music feels resolved and “at home”. It is C major if the chord is C (major). The key is E minor if the chord is Em (minor). The tonic chord is also known as the root chord.
The tricky part is that this is not always the first chord or the last chord of a song. It is also common for songs to change keys. Some songs are non-diatonic (not of the scale; i.e. they do not follow most conventional rules of harmony), in which case a large number of chords are not determined by the key center. With a few exceptions, most songs are mostly diatonic, with the exceptions usually being the most interesting and unique parts.
You should trust your ear
It’s never wrong to play something beautiful, a great teacher once told me. Embrace adventure and discard fear. There is little chance that anyone will die, much less even get injured, since it is only music.
Maybe someone else will drop by with a better answer. However, if you come across a chord that feels like “home”, it’s likely that chord is displaying the song’s key.
Quick Questions
Do all songs have a key?
Songs are written in specific keys that determine the chords and notes that work well together. Improvise, transpose, or write songs if you know the key.
What are the 7 keys in music?
Western music has seven modes of the major scale (Ionian, Dorian, Phrygian, Lydian, Mixolydian, Aeolian, and Locrian).
Is the key of a song important?
When you know the key and scale of a song, you will be able to build a chord progression that harmonically supports the melody. Note choices for the bassline. In addition to knowing the key and scale, you will also be able to choose which notes to use for the bassline. The root notes of a chord progression are commonly used to build a bassline.
What is the highest key in music?
It’s C8 the highest key on a standard 88-key piano.
What are all the 12 keys in music?
In Western music, there are 12 notes: C, D, E, F, G, A, B, as well as five flats and equivalent sharps in between. These notes are C sharp/D flat (they are the same note, named differently depending on the key signature), D sharp/E flat, F sharp/G flat, G sharp/A flat and A sharp/B flat.
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