Learn The Chord System Behind Almost Every Song You Love

Added: 2026-05-13

[00:00:00]All right. The thing I'm about to show you is so valuable as a musician, a guitar player. This can be for understanding music in general, music theory, songwriting.

[00:00:11]It's it's a gamecher. Now, nowadays, it's called the Nashville number system, but it's been around a lot longer.

[00:00:17]Nashville number system is kind of a specific um angle of uh what I'm going to show you. But basically, I'm going to show you the chords of a key. That's what it is. Um, and I'm going to show it to you in the key of C.

[00:00:37]It's a set of chords that come from a scale, the major scale.

[00:00:50]They're related. Um, now the Nashville number system term is specifically because in Nashville when people are, you know, it's a big songwriting city, Nashville. And so when people write songs, they use the name that corresponds with the the degree of the key that it comes from. And instead of saying, well, the song is C to D minor to E minor, they say, oh, it's a one, it's a two, it's a three. Because then that way when you change keys, because singers need to sing in different keys, if you're just going by the numbers and you say, "No, actually, well, um, I changed the key. It's in the key of E.

[00:01:28]Um, it's in the key of F now." You can still play the same relationship of 1 2 3 4 5. So that way you don't have to rewrite a chart. That's one reason. But anyway, we're going to talk about this natural number system. I'm going to break it down and uh I recommend you sticking around for the whole thing.

[00:01:48]It's going to be super valuable. Also, I have an ultimate guitar guide, which is the whole foundation of guitar in a free PDF book. It's in the link below. I got a website, martymusic.com as well. You should check it out. Okay. So, in a scale, and the reason we do C major, or I'm going to show it to you in C major, is because there's no sharps or flats in the scale C major or the key of C major.

[00:02:14]That means that as a more beginner guitar player, you don't have to play any bar chords or move the guitar around. It's all basic open cowboy chords. Okay? So, there's a scale called the major scale. Also, it's that do reay me do reo.

[00:02:34]Notice I started and ended on do do.

[00:02:42]Those are the same notes. D. Each name is the note of the scale. So there's seven notes in the scale.

[00:02:49]Four, five, six, 7. 1 2 3 4 5 6 7 1 2 3 4 5 6 7 1 and it goes on and on in octaves, but it's seven notes and then it starts over again. Each of those notes is the root and the name of a chord from that key.

[00:03:14]So, what's cool about that is that the scale is like the DNA They feel like they all go together, right? They You can hear that they go together as opposed to Right. All of a sudden that sounds unfamiliar. That was a note not in the scale.

[00:03:48]Although you can break rules for music theory and drama dramatic um composition as well but it starts with understanding this basic foundation. So the scale you can think of as the DNA and then when you put the DNA into combinations only from the DNA then each of the chords sound like they go together. And so there's seven notes C, D, E, F, G, A, and B. And that's specific to the key of C major. If I played um G sharp major, it would be G sharp, A sharp, C, C, C sharp, D sharp, etc. So it's different.

[00:04:31]But C major is just the natural notes.

[00:04:33]In fact, when you look on a piano, C, D, E, F, G, A, and B, those are the white keys all in a row. No black keys.

[00:04:42]So 1 2 3 four five six and seven. The seven degrees of the scale. Instead of saying the letter, I could say the one, the two, the three, the four, the five, the six, and the seven. Back to the one again.

[00:05:02]So each of those roots is the uh each of those notes is a root to a chord in the major key. And most songwriters will use a combination of these chords to make their chord progression because they sound good together. And then there's like classic progressions like 145, uh 62 51 um etc. you'll hear these terms. Um, and so the rules are always the same and the formula and the distances are always the same. So if you know this concept, you can start writing your own songs. And then obviously there's rules that go beyond this basic concept, but you got to know this basic concept to then go to the next level, right? So here's what's cool. The chords that are used, you know, 95% of the time are actually just the first six chords. The seventh chord, which is called a minor 7 flat 5, it's not typically used in basic songwriting or songwriting almost at all. Yes, it's used sometimes, but almost never. And for a intro lesson like this, never.

[00:06:16]We're not don't even want to think about it. So, here's what we got. We got the one chord. And in the key of C major, the one chord is a C major chord.

[00:06:29]All the notes making up that chord come from.

[00:06:39]So I'm taking that DNA, the scale, and harmonizing notes from it to make the first chord. Now, in any key, the one chord in any key, you know, B flat major, F major, the one chord is a major chord. So, if we're in B flat major, the one chord is B flat major. If I'm in the key of A, the one chord is A major. So, the relationships always stay the same.

[00:07:03]Back to C major. C is the one chord.

[00:07:09]C major. The two chord in a key is always a whole step up and minor.

[00:07:18]So the one chord is major. The two chord is a whole step up, meaning skipping a fret or skipping a note. And then it's always minor. So in the key of C major, the two chord is D minor.

[00:07:33]So one chord, two chord is minor.

[00:07:39]The three chord is a whole step up from the two chord and it's minor as well. So a whole step up from D is E. And so the three chord of C major is E minor.

[00:07:53]So in the key of C major, one chord is C major.

[00:07:58]Two chord is D minor, which I like to use the bad English accent D minor from Spinal Tap. It's the saddest of all keys. D minor.

[00:08:08]The three chord is E minor.

[00:08:12]And here's where we get to the four chord. The four chord is always in a major key. The four chord is always a half step higher than the three chord and it's major. So in the key of C major, we have C, D minor, E minor.

[00:08:31]Half step up is an F and it's F major.

[00:08:34]And I'll play it this kind of folk F major. I like which you know you could play a bar chord if you can do it this way is just eliminating the two E strings and you don't have to play a bar. So it's third fret, third fret, second fret, first fret.

[00:08:56]That's the four chord. The five chord is always a whole step up from the four chord and it's major. So G major.

[00:09:05]Now, there's something special about the five chord. Right now, we're playing G major. The five chord in any key, any major key, the five chord, it is major, but it can also have a fourth um color added to it called the flat 7 or the dominant 7. So, the five chord could be G major, but you can add an extra note to it and it would become G7.

[00:09:30]Not G major 7, not G minor 7. You just say the word, the letter and the number G7. That's implying this kind of more bluesy sounding chord.

[00:09:44]And what's cool is it adds a little extra tension that wants to resolve on the one chord. Listen to that.

[00:10:00]So one chord is C. Two chord is D minor.

[00:10:04]Three chord is E minor.

[00:10:07]Four chord is a half step up and major.

[00:10:11]Five chord is a whole step up major or dominant 7.

[00:10:18]Or you can make it major then add the dominant 7.

[00:10:26]and feels resolved at one at the one.

[00:10:28]Okay. So we have the five chord is G or G7.

[00:10:33]The six chord is a whole step up which a whole step up from G is A and it's minor. So A minor.

[00:10:44]And remember I said the seven chord is not used. Hopefully you do remember that. But if not I'll tell you again.

[00:10:49]The seven chord is not used and it's called minor 7 flat 5. So I play B minor 7 flat 5.

[00:11:05]And we don't want to worry about that right now and not add extra information.

[00:11:09]That's the seventh chord. And then the seven to the one is a half step again.

[00:11:15]So 1 2 3 4 5 6 7 1. Now here's the interesting thing about that seven chord. Even though we're not using it, if I play that, but then I add a G in the bass.

[00:11:35]It's functioning as a G7 again.

[00:11:38]So you could even hear the scale in chords.

[00:11:46]by going C, D, uh, D minor, E minor, F, G7, A minor, G7, C.

[00:11:55]Listen to that.

[00:12:14]And so if I wanted to play, let's say I came up with a progression, uh, one chord, five chord, six chord, four chord, one chord, five chord, four, down to one. 1 5 6 4 1 5 4 down to one. Then the six to the five to the four to the one one to the five four down to one.

[00:12:59]So, let's say I wanted to play that progression, but I wanted to play it in D major. Right now, we're in C major.

[00:13:06]Well, I just have to move it up a whole step. Let's say I don't know bar chords.

[00:13:10]I don't know theory, but I know those basic numbers of C major. Well, I can put the capo on the second fret, one whole step up. And now every chord is a whole step higher, even though I'm playing the same thing. 1 5 6 4 1 5 4 down to one. Then the six to the five four to the one again to the five and the four down to one.

[00:13:48]Same thing. I can move it around and use those number relationships and playing a new key by just knowing the numbers. And most songs that you love will be using that concept. But then there's chords and chord changes and modulations and all these other things. They're not even breaking the rules. There are other compositional tools that are based off of the understanding of what I just showed you.

[00:14:16]So you got to know this first to then branch off into more complex um compositional techniques. For instance, the four the one chord is C. The four chord is F. Or I could say a minor four chord. So let's see one to the four to the minor 4 to the one.

[00:14:42]I have to know what the four chord is first before I know the minor four chord. Okay. Uh Bob Dylan, most of his songs are just coming from the six chords. But one that's really cool is like a Rolling Stone just goes up the chords of the key of C major. 1 2 3 4 5 and then 145. There's other parts, but 1 145 is the chorus. 1 4 5 1 2 4 5. Another interesting thing though about this is you can use this these six chords and write a progression, but that doesn't start on the one chord. I could even have progressions using this key and scale and not even have the one chord in it. I could do a six Uh, let's see. I can do a six to a two to a three. Listen to that.

[00:15:59]Or let's say I'm just being inspired and I come up with a progression and I'm not thinking about the numbers at all, but I just let's say I did come up with A minor, D minor, and E minor. And I started working on something. I like that. Okay. Where else can I go? Well, I think D minor. Let's try.

[00:16:17]Okay. E minor. Why not?

[00:16:35]Well, then I could stop and go, what what key? I don't even know my theory that well, but those chords go together well. And I start to realize, oh, those are all from C major.

[00:16:46]So, I can use some of the other chords from that to come up with a new section.

[00:16:50]So, let's say So, you have six chords to be creative with. You know, how much time do the chords pass? Could you go quicker?

[00:17:56]You know, I'm just not even thinking about anything. I'm just let I know the chords of that key and I'm just start experimenting and come up with something. And sometimes you'll love it, sometimes it's not that inspiring, but those are the chords that sound good together. So to recap, what we just did was we learned the natural number system is one way to look at it or just the chords of a key of a major key. And there's six of them that are used and it's one and in the key of C major it' be C major is the one. D minor is the two.

[00:18:27]E minor is the three.

[00:18:30]F major is the four and it's a half step up from three.

[00:18:36]Five is major or dominant 7.

[00:18:40]And six is minor. A minor.

[00:18:44]And you can put them in any combination and they'll sound good together. And you don't even have to always start with the one. So, I hope that made sense. Once again, my whole thing, I've been teaching guitar for 30 years now, but uh specifically making YouTube videos for 18 years now, and it's gone a lot longer than I expected, but I still love it.

[00:19:06]Love helping people. And I can help you more at my website, martymusic.com.

[00:19:11]In fact, I've got a community over there where I do um uh like a live stream master class two to three times a month and the students can actually chime in on video and ask me questions. And that's been under a year as of making this video and it's been an amazing new aspect to what I do, being able to talk to people, answer their questions, and relate to everybody. So, you can um check that out. Plus, I have a ton of courses at my website, martiammusic.com.

[00:19:38]So you can do like a monthly membership where you get those live master classes or if you're just there's a topic you're interested in, you can just buy one of the courses allocart, no recur no recurring fees or anything and buy uh like a beginner acoustic or you can buy music theory or learn how to play lead guitar, blues, intermediate beginner stuff. It's all there. So check the links below. Thanks for supporting and hope to see you guys again real soon.

[00:20:04]See you later.