Recognising Keys by Chord Sequences

Hello @MikeGor and welcome to the Community.
At that time in the video Justin has just played a D and E chord and improvises (literally makes something up on the spot by playing random notes) using the A major scale. He is not even thinking or giving it a careful ear to make it sound really good. He is just demonstrating that the A major scale can be used over those two chords - because they are the IV and V of A major.

If you hear it sounding like a well known song I can say with great certainty it is just a coincidence and not at all intended.

Cheers :smiley:
| Richard_close2u | Community Moderator, Official Guide, JustinGuitar Approved Teacher

Anyone got a few easy songs to recommend?

Hello @whernan1 and welcome to the Community.

You could literally take your pick from any of the songs here and filter by Grade (say 1 and 2 more than 200 songs).
!

Then check the chord progressions (use the chapter select tool) and write down the main progressions. That should give you lots to start with.

Hope that helps.
Cheers :smiley:
| Richard_close2u | JustinGuitar Moderator, Guide & Approved Teacher

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Cool, I didn’t know about this, i’ll check it out, thanks Richard!

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I decided to try working out the key of “Landslide” from the chords. Just thinking out loud/showing my working in here, rather than responding to the lesson. Happy to move or ditch the post if this isn’t the right spot for it.

The chord patterns in the song seem to be:

Verse: C - G - Am7 - G
Chorus: C - G - Am7 - D - G - D - Em - Em

At first I was thinking it might be in C, since that’s the first chord, but the D major chord doesn’t fit that key (in the key of C the ii would be D minor).

Then I looked at the key of G. In that case all of the chords fit in the key:

I - G
ii - Am (as a minor seventh)
iii - Bm (not used)
IV - C
V - D
vi - Em
vii - F#m (not used)

If it is in G, that would make the chord progressions

Verse: IV - I - ii7 - I
Chorus: IV - I - ii7 - V - I - V - vii - vii

Apparently a minor seventh built on the ii is pretty common and also naturally resolves to the V, which does happen in the chorus.

All seems to point to a solid fit in the key of G.

@direvus
Your logic, thinking and application are exactly right. Everything on paper points to the key of G for the reasons you brilliantly provide.
That said, paper calculations are not the only factor. Your ear and some other considerations need to be used.

Verse: C - G - Am7 - G

The way you have it written out the verse seems to finish on the G chord, so our eyes may see that as being where the progression resolves - G as ‘home base’.
However, within the verse that is not the case. The progression loops around and around. G is a chord that connects C to Am7 and back again. Strictly speaking it is G / B and the B note in the bass gives a run down from C to B to A then back up again from A to B to C. If you were to actually play that progression through and finish on the G it would not sound resolved. It does sound resolved on the C chord and the verse is in C major.

Verse:
| C G/B | Am7 G/B |

| C G/B | Am7 G/B |

| C G/B | Am7 G/B |

| C G/B | Am7 G/B |

The transition to the chorus follows the verse movement but instead of climbing back up to C it moves from Am7 to D7/F#

Verse ending (leading to chorus)

| C G/B | Am7 D7/F# |

Chorus:
| G D7/F# |Em | C G/B | Am7 D7/F# |

| G D7/F# |Em | C G/B | Am7 G/B |

Again, the slash chords give a moving bass line that connects the chords melodically. This seems like a key change and the song has moved to the key of G, as your analysis suggests. Although the vocal melody does not make use of that F# note so can be seen as staying within the same key of C throughout. In which case the entire song can be seen as staying in the key of C throughout and the D7/F# could be better described as a borrowed chord or as a secondary dominant chord. The verse is not clear cut.

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Oh wow. I guess I could have picked an easier song for my first try, eh? :laughing:

I had no idea these were slash chords. I wrote down the chords from the JG app, where they are shown without a slash. Next time I play I’ll definitely try throwing in the slash versions and see how it changes the sound.

Thanks so much for your detailed response Richard, I learned a lot from this.

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Ok. Let me see if I am understanding this;

  1. Look at the chords in a song
  2. Look for major chords which could be IV & V of a particular key (or minor II & III)
  3. Play the notes from the scale relative to that key (E.g. song in G Maj then play notes from G Maj scale) over that song and should sound right. Right?

@Colberg69 - a fair summary Colin … although …

I have added a little more info plus, minor chords are most helpfully denoted as lower case, so ii and iii.

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Thanks Richard.
Now I’m clear I understand this concept I’m off to give it a try.

Thanks again

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And another thing; Question 1 shows Amin, D, Emin.
Now all those chords fit in GMaj but they don’t follow Justin’s pattern 1, 2 or 3 (I think).
Does it follow then that aside from the 3 patterns suggested you can also simply see which key the chords fit into?

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Yes. E is the perfect fifth of A, which can be written like this: [scale degree of A] + 4 = [scale degree of E].

As both chords are minor, they can be either degree II, III or VI. Out of these options, the above formula fits degrees II and VI, so Am is the II chord and Em is the VI chord, and we’re in the key of G major.

The same applies to the I and V chords as well, i.e. D is the perfect fifth of G and both chords are major.

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Thanks Jozsef,

Maybe that was a little test inside a test by Justin to talk about Pattern 1, 2 & 3 and then giving the first equation that doesn’t fit any of these patterns.

Cheers

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I’m completely lost trying to work out the answers to the quiz. Everything up until this point has sunk in but Ive just hit a brick wall. I’m sorry if this is a stupid question, but can anyone break it down for me a little better. I got 1 out of 10 on the quiz and Im pretty sure I fluked the one I got right. I am just completely confused. So Ive stopped the lessons (I usually complete a whole Module before I begin working on it) and Ive come here for some guidance. Any help would be greatly appreciated. Thank you in advance.

Hey Adam,

There’s no stupid questions here mate.
One suggestion which may help is to work backwards, so to speak.

Using Question 1 as an example ( Am, D , Em). From the answers, you can see it’s G Major.

  1. Write out the G Major scale

GABCDEF#

  1. Underneath, write out the chords.

I ii iii IV V vi vii
G Am Bm C D Em F#°

(forget the vii for now, just here for completeness)

  1. Reconcile in your mind how the answer is derived.

Repeat for the other questions. This stuff takes a while to internalise. Mainly just time, practical use, and repetition.

Cheers, Shane

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Hey Shane,
Thank you so much for taking the time to respond. Ive given up for today but Ive copied and pasted youre response into my notes and Ill try it that way tomorrow. I find sometimes when I hit a wall like this, its best for me to put it aside and try again another time. But again, thank you so much for your response. I really truly appreciate you taking the time for me. Cheers my friend!

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Hey Shane,
I did what you suggested and it worked beautifully, so thank you so much again. But just one thing. How do I get to the correct answer without knowing it? Is it just a case of trial an error, of running through the different keys until I find the one that matches or is there some giveaways that help narrow down the field? Thanks again for your time!

Hi Adam,

The major scale formula and the diatonic chord formula for major keys will help you:

Intervals in the major scale (starting on the root note): T T S T T T S

I, IV, V: major
ii, iii, vi: minor
vii: diminished

So if you have a chord progression like the one above with Am and Em, you will know which chords they can be and deduct the key you are in (see my previous comment a little above).

By applying the above rules, which key do these diatonic chords belong to: Cm, Eb, Gm?

Ab Major?

I only know that though because I just worked on Question 3 which was in that key and it had those 3 chords when i wrote out the I - VII. If I hadnt have had that example in front of me, I wouldve had to go through all the Keys to find the one which matches. Or is that just what you have to do until this stuff starts sticking in your memory through repetition?

Thanks heaps for your comment by the way. I really appreciate you taking the time to message me and help me with this. Yours and Shanes’ comments have helped me get through a part of the theory that had me head in hands saying this is too hard yesterday, so Im showing progress. Cheers mate!

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You’re welcome :slight_smile: But it’s not Ab major :innocent: