Identifying a key

Hi,

I am having a great time on this site and just moved on from fundamentals onto rock lessons.

Had a quick question, I understand the Key chord identification structure of 1st, 4th & 5th, simple enough, and also understand that although usually the first note/chord played is the key a tune is in it doesnt always work that way. I know you can play a song in a key and but start with a note/chord that is not in that key.

But what if you create a tune that doesnt follow the 1, 4, 5 structure? I came up with a part of a tune (only very short) of Amaj>Amaj flat>C#minor (barre chords)>A (rock open)>C(open)>B7>Emaj. How do I figure out what key it is in as there is nothing in there that fits into the 1,4,5 format but still sounds okay that the chord progression works ?

Sorry its a bit of a fiddly question.lol.

Hey, glad you are enjoying GT!

Originally Posted by: adamstocker

But what if you create a tune that doesnt follow the 1, 4, 5 structure?[/quote]

I, IV & V are the most commonly used chords in a progression. But you can form a chord on any of the 7 notes of the major scale. And you put them in any order you want. Later you will find there are 12 possible chromatic notes on which you can build an incredible variety of chords! And you can combine them in any way you desire.

There are general practice standards for how chords are combined. I cover the basics of this aspect of music theory in this tutorial.

https://www.guitartricks.com/tutorial.php?input=495

Originally Posted by: adamstockerHow do I figure out what key it is in as there is nothing in there that fits into the 1,4,5 format but still sounds okay that the chord progression works ?

You write out all the notes of all the chords you are using & see if they form all or most of a scale. It also helps a great deal if you have a melody because that is a very strong indication of the key signature.

This is the essence of what a key signature is: the scale that contains all or most of the notes of a song, melody, or chord progression.

I cover this topic in my intro to improvisation tutorial.

https://www.guitartricks.com/tutorial.php?input=876

[quote=adamstocker]

I came up with a part of a tune (only very short) of Amaj>Amaj flat>C#minor (barre chords)>A (rock open)>C(open)>B7>Emaj.

A: a, c#, e

A-flat: a-flat, c, e-flat

C#min: c#, e, g#

C: c, e, g

B7: b, d#, f#, a

E: e, g#, b

a, b, c, c#, d#, e, f#, g, g#

We don't need to include a-flat because it's the same note as g#. Also d# is e-flat.

Most of those notes are in tlhe key of E major:

e(1), f#(2), g#(3), a(4), b(5), c#(6), d#(7)

Some are not:

c(minor 6th in E minor), g(minor 3rd in E minor)

But they are in the closely related, parallel key of E minor! So the progression has some modulation, notes and, or chords that are not in the same key as the rest of the notes.

So using E as the root we get this:

A (IV) - G# (III or V of VI) - C# min (VI) - A (IV) - C (bVI) - B7 (V) - E (I)

Stripped down this is a IV-VI-V-I progression with some modulations to make it interesting.

G# is a modulation that leads to the C# minor. C is a modulation that leads to the B. I cover this kind of secondary dominant relationship in the music theory tutorial linked above.

Most of how this works is in the tutorials listed above. Please ask more if necessary. Hope that helps!

Originally Posted by: adamstocker

Hi,

I am having a great time on this site and just moved on from fundamentals onto rock lessons.

Had a quick question, I understand the Key chord identification structure of 1st, 4th & 5th, simple enough, and also understand that although usually the first note/chord played is the key a tune is in it doesnt always work that way. I know you can play a song in a key and but start with a note/chord that is not in that key.

But what if you create a tune that doesnt follow the 1, 4, 5 structure? I came up with a part of a tune (only very short) of Amaj>Amaj flat>C#minor (barre chords)>A (rock open)>C(open)>B7>Emaj. How do I figure out what key it is in as there is nothing in there that fits into the 1,4,5 format but still sounds okay that the chord progression works ?

Sorry its a bit of a fiddly question.lol.

That was a fun exercise Adam! I did more or less the same thing that Christopher recommended and came up with almost the same answer. Well, I initially thought A which has nearly as many notes (1 less) than E when compared to your progression. But on closer inspection and guided by Chris's analysis, I agree that E is the better option. In listening to it, the final two chords (B7-E) sounds like a finish. That is to say, when you hear the E, it sounds like you have come home and can put on your slippers and call it a night.

Anyway, to amplify and extend what Chris said (and hopefully not say anything incorrect):

(1) when analyzing a progression with the intent of identifying a key, you can somewhat disregard chords that aren't in the key if they are a dominant chord (often but not always a dom7) to the chord that follows (i.e., if G7 is followed by C, A7 is followed by D, B7 is followed by E, E7 is followed by A, D7 is followed by G, etc [note that if you count up from each of the final chords to the preceding chord you go up 5 letters - i.e., a perfect 5th]). That dominant chord is often inserted whether it is in the overall key or not (if it's not, it's called a secondary dominant) because it has the effect of propelling you to the chord that follows (which is in the key) which is quite useful musically and helps create flow. Maybe that sounds like gibberish right now, but the tutorial Chris pointed you to goes over this in more detail and explanation. There are lots of other specific instances in which an out-of-scale chord is used, but that "secondary dominant" is probably the most common.

(2) Songs can often change keys, especially at clearly identifiable breaks in the song structure - like between the verse and the chorus. It's kind of a cliche, but not uncommonly the key will just go up in pitch (even if it's just a semi-tone or so) somewhere towards the end of the song (possibly with the goal of signalling that the end is coming and pumping a little more energy into the last bit to to maintain the listener's interest). So if chords, overall, don't fit well in any given key, it may help to look at different parts in isolation, or to see if there is somewhere during the course of the song where unexpected chords start showing up.

(3) Also, from what I have read, not all songs are written in a key. Some rock songs for example, have relatively simple chords that shift up and down in pitch in such a way that any attempt to identify a key would result in so many out-of-key notes that a key-based analysis would be more trouble than it's worth. For example, a song may use a series of major chords, or power chords, that are rooted on the notes of the minor pentatonic scale - chords like C major, D# major, F major, G major, A# major. So the chords kind of move in parallel. You might be able to make C sound like home base, but it's not a C major scale that you are playing in. Having said that, in my limited experience, that is not nearly as common as key-based songs.

Just seeing it on paper, I didn't think I'd find that progression very musical, but I played it and really liked it a lot!

When determing a key from a chord progression these rules apply (in diatonic keys):

1. two minor chords a full step apart are ii & iii chords

2. two major chords a full step apart are IV & V chords

3. a minor chord and a major chord a half step apart are iii & IV chords

4. a minor chord and a diminished chord a full step apart are vi & vii° chords

With these rules a root chord of a MAJOR key can be determined. There can be out of a key chords in progression, but the rules still apply. If the song is in minor, then relative minor is a root.

Originally Posted by: ChristopherSchlegel

Hey, glad you are enjoying GT!

Originally Posted by: adamstocker

But what if you create a tune that doesnt follow the 1, 4, 5 structure?[/quote]

I, IV & V are the most commonly used chords in a progression. But you can form a chord on any of the 7 notes of the major scale. And you put them in any order you want. Later you will find there are 12 possible chromatic notes on which you can build an incredible variety of chords! And you can combine them in any way you desire.

There are general practice standards for how chords are combined. I cover the basics of this aspect of music theory in this tutorial.

https://www.guitartricks.com/tutorial.php?input=495

Originally Posted by: adamstockerHow do I figure out what key it is in as there is nothing in there that fits into the 1,4,5 format but still sounds okay that the chord progression works ?

You write out all the notes of all the chords you are using & see if they form all or most of a scale. It also helps a great deal if you have a melody because that is a very strong indication of the key signature.

This is the essence of what a key signature is: the scale that contains all or most of the notes of a song, melody, or chord progression.

I cover this topic in my intro to improvisation tutorial.

https://www.guitartricks.com/tutorial.php?input=876

[quote=adamstocker]

I came up with a part of a tune (only very short) of Amaj>Amaj flat>C#minor (barre chords)>A (rock open)>C(open)>B7>Emaj.

[p]Let's apply the concept.

A: a, c#, e

A-flat: a-flat, c, e-flat

C#min: c#, e, g#

C: c, e, g

B7: b, d#, f#, a

E: e, g#, b

a, b, c, c#, d#, e, f#, g, g#

We don't need to include a-flat because it's the same note as g#. Also d# is e-flat.

Most of those notes are in tlhe key of E major:

e(1), f#(2), g#(3), a(4), b(5), c#(6), d#(7)

Some are not:

c(minor 6th in E minor), g(minor 3rd in E minor)

But they are in the closely related, parallel key of E minor! So the progression has some modulation, notes and, or chords that are not in the same key as the rest of the notes.

So using E as the root we get this:

A (IV) - G# (III or V of VI) - C# min (VI) - A (IV) - C (bVI) - B7 (V) - E (I)

Stripped down this is a IV-VI-V-I progression with some modulations to make it interesting.

G# is a modulation that leads to the C# minor. C is a modulation that leads to the B. I cover this kind of secondary dominant relationship in the music theory tutorial linked above.

Most of how this works is in the tutorials listed above. Please ask more if necessary. Hope that helps!

Hi Christopher,

Thanks for the detailed response. I will admit I am at a point in my training where a lot of that went over my head due to the knowledge gap. I understood though the core of it re. writing down the notes of each chord and referencing them to a scale that incorporates the majority of them as a key idenitfier, that is handy to know. Beyond that I will have to wait until I get to that point in my training as I mentioned to understand the rest clearly. I like to take things a step at a time in case it blurs my founationary knowledge. Thanks again.

Originally Posted by: jarkko.eklund

When determing a key from a chord progression these rules apply (in diatonic keys):

1. two minor chords a full step apart are ii & iii chords

2. two major chords a full step apart are IV & V chords

3. a minor chord and a major chord a half step apart are iii & IV chords

4. a minor chord and a diminished chord a full step apart are vi & vii° chords

With these rules a root chord of a MAJOR key can be determined. There can be out of a key chords in progression, but the rules still apply. If the song is in minor, then relative minor is a root.

Thanks for the response, would you mind giving and example on each point you mentioned please to cement my understanding? Thanks.

You're welcome for the reply!

Originally Posted by: adamstocker

I understood though the core of it re. writing down the notes of each chord and referencing them to a scale that incorporates the majority of them as a key idenitfier, that is handy to know.

Best of success!

Originally Posted by: adamstocker

Thanks for the response, would you mind giving and example on each point you mentioned please to cement my understanding? Thanks.

Jarkko's reply is a quick, handy way to look for relationships among chord groups. Because all major scales have the same interval formula, harmonizing every one of them always results in the same relationship of chord qualities.

I (1) chord is always major

whole step up there is always

ii (2) chord is always minor

whole step up there is always

iii (3) chord is always minor

half step up there is always

IV (4) is always major

whole step up there is always

V (5) is always major

whole step up there is always

vi (6) chord is always minor

whole step up there is always

vii diminished (7) chord is always diminished

half step up is

I (1) chord is always major

Examples!

If you have an A major chord and a B major chord in a progression, those are 2 major chords a whole step apart. They must be the IV & V chord in E major.

If you had C major & D major, those are 2 major chords a whole step apart. They must be the IV & V chord in G major.

If you had D minor & E minor, those are 2 minor chords a whole step apart. They must be the ii & iii in C major.

All this is covered in my tutorial on harmonizing the major scale. Hope that helps!