This lesson covers the problem of finding the key of a tune. Many people try to work out the key of a piece while transcribing or often just wonder what it is within a tune that informs us of the key. In this lesson, I’ll be covering several different methods for working out a key using key signatures, scale, arpeggios, chord progressions and our ear.
3 Common Scenarios
There are three situations that require slightly different tactics to find the key of a song:
- working out a song or key by ear
- reading sheet music
- reading a chord chart
Working Out The Key By Ear
Working out the chords and playing through the bass line can help you find the key as the tonic (root note or chord), normally feels like home. This means that the song or section may feel resolved when it reaches that chord.
Songs very often begin and/or end on the tonic so this is another way to find out the key. If the ending of the song doesn’t finish on the tonic then you should be able to hear this as it will sound obvious.
The tonic chord is often (but not always) the first chord of the song and usually always the last.
Sheet Music
The easiest way to tell the key of a song from the notation is by looking at the key signature. This is represented at the beginning of the stave by a series of flats or sharps (or nothing in the case of C major/A minor).
Here is a list of the key signatures for major keys:
Sharp Keys
Flat Keys
Minor Keys
Key signatures are a great starting point for working out the key, but they don’t always give us all the information. If a song is in a minor key, it will share the same key signature as its relative major.
- The relative minor of a major key is found on the sixth degree of the major scale
- The relative major of a minor key is found on the third degree of the minor scale
Here are the key signatures again with the relative minors included:
Sharp Keys
Flat Keys
So how can you tell if a song is major or minor if they share the same key signature?
Look for a tonic chord. If a song starts and ends on a G major then it is very likely that the song is going to be in G major.
It is also worth noting that minor keys often use the harmonic (raised 7th) and melodic (raised 6th) minor scales. Spotting these altered notes in the bass line can indicate that the song is in a minor key.
Chord Charts
Most people don’t actually know the key of a piece when playing from a chord chart as it is possible to get by without it. However, if you want to really understand the piece and be able to improvise over it confidently then you need to know the key. Chord progressions can be one of the best and most obvious methods of finding the key.
Having a knowledge of the chords in each key will help the key of a song jump out at you quickly. Develop an eye and an ear for harmony in this way by learning the diatonic chords within a major and minor key. Take a C major scale for example:
C D E F G A B
We can number the degrees of the scale like this:
C D E F G A B
1 2 3 4 5 6 7
We can then build chords on each degree to give us a full pallet of chords for that key. There is more information about how to build chords by stacking thirds together in the music theory for bass series on talkingbass.net.
The chords in C major are:
- C Major
- D Minor
- E Minor
- F Major
- G Major
- A Minor
- B Diminished
Remember This!
- Chords I, IV and V are always major.
- Chords ii, iii and vi are always minor.
- Chord vii is always diminished.
Extended Chords
We can extend these chords by adding a 7th to each one.
- Cmaj7
- Dm7
- Em7
- Fmaj7
- G7
- Am7
- Bm7b5
Notice how chord 5 has now become a dominant chord. This is a really useful way to spot the key of a tune as the dominant chord is found on the fifth degree of every major scale. So if you see a G7 then you can count backwards to find the root note (C). This is not always true but it is a general rule and is a good place to start.
Thanks Mark. Absolutely great lesson and so well explained. I’ve always had problems trying to explain to someone how to find the key of a song. I know now how to explain it clearly. Thanks again and i am so looking forward to the future here at talking bass.
Martin
The lesson material for this lesson (and also the lesson on note control) download as “chromatic technique building” , not material associated with the lesson. Can you help?
As Bob Fletcher told before this lesson material is not correct
:/
where is the pdf?
PDF :/
22:00 error :/
Hi there. What is the error at 22:00?
First time of my life that I completely understand this subject..many many thanks!!!
PDF?
hey Mark, love the site, but as a few people have said there is no PDFs in the lesson material anymore. This is true for a number of lessons.
One important question regarding the key signatures:
Why F# mayor is shown with 6 sharps but Gb major with 6 flats, when F# and Gb is the same note?
The same goes for Cb / B major or C# / Db major.
Thank you in advance.
This is an old question, but I ran into this recently so…..I think this is the “alphabet rule”. When you have a scale the notes have to be in alphabetical order (abcdefga) so one note can have 2 names. In Emaj the note after E has to be an F(#) even though it is the same note as Gb. In the scale of Eb min the first 3 notes must be E(b), F…and G(b). They call it a rule though it seems more like a naming convention. Apparently it can have real impact in some situations we won’t encounter with fretted instruments.