Play by Numbers

By David Hodge

Knowing chords by number can help you play any song in any key—using chords you already know. Web exclusive! Printable chord transposition chart

Click here for downloadable transposition chart

You’re listening to your favorite CD, and suddenly, it hits you. “That is the next song I’m going to play on guitar,” you say to yourself. You know you can do it. You’ve got your basic chords down and are doing pretty well at changing from one to another. How hard can this song be? So you hunt down a transcription, and you’re really excited when you see the song only uses four chords—until you see that those chords are Fm, Ab, Db, and Eb. What?!?!

Fortunately, you’ve got two good options: you can learn the chords you don’t know and expand your chord vocabulary or you can do what most guitar players would do—transpose the song into a different key so you can play it with the chords you do know. With a basic knowledge of keys and chords, you can create a generic chord progression that uses the Nashville number system, which uses chord numbers instead of names.

1. Determine a Guitar-Friendly Key
Some chords are just easier to play than others. Open-position chords, which use one or more open strings, are the staple of guitar music because they’re the easiest to play. That’s why you often run into E, Em, A, Am, D, G, and C chords in easy guitar music.

When the main chords in a key (a grouping of chords and notes) are open chords, players tend to think of those keys as guitar-friendly. Keys like C, G, D, A, and E are pretty guitar-friendly keys.

But not all music is written in those guitar-friendly keys, so you’ll want to convert the unfriendly chords in one key into the familiar open-position chords you’re comfortable playing. This conversion, by the way, is called transposing.

2. Pick a Number
The easiest way to transpose is to think of your chords in generic rather than specific terms. To show you what I mean, I've written out the notes of a C-major scale below. Instead of using the note names, let’s assign each note a number so that C becomes 1, D is 2, and so on.




Substituting numbers, which are the same as the scale degrees, for the chord names is called Nashville numbering, because it’s been a staple of Nashville recording sessions for ages. Like those Nashville cats, you can use this system to easily transpose a chord progression or an entire song.

3. Try Transposing
Suppose you’re playing a standard 12-bar blues song in C. The song would look like this:




When we convert this to Nashville numbers, we get this:




Now pick a key, any key. How about A? Here are the scale degrees of the key of A:




Let’s substitute our chords from the key of A for the same numbers in the key of C, so we can now play the blues in A:




The thing to remember about transposing is that you’re only changing the letter name of the chord. All the other baggage that comes with a chord—whether it’s minor, major, a seventh, etc.—will stay the same. Minor chords are noted by placing a - after the number. Things like sevenths, ninths, and other embellished chords have small numbers (like exponents) following the main number.

So say we have a progression in the key of C, like the one below, but you want to play it in G. First write the chords out as numbers. Then, taking a look at the notes of the G scale, you could easily translate those numbers into the key of G.



Transposing can be this easy! If you already know a few songs, you’re ahead of the game because you’re familiar with some of the many common chord progressions found in songs. When you look at the numbers, you’ll realize that the G–C–D or A–D–E patterns are both 1, 4, 5, while something like C–Am–Dm–G or D–Bm–Em–A (think of “Stand by Me” or Pearl Jam’s “Last Kiss”) are both 1, 6-, 2-, 5.

4. New Year, New Key
Many holiday songs are written in non-guitar-friendly keys, so transpose a few and you’ll have songs for your family and friends to sing along. Let’s take a look at the New Year’s classic “Auld Lang Syne,” which for whatever reason is in the key of Eb in the book I have here at home:



I’m pretty sure you’d rather play this in an easier key, right? So let’s convert our chord progression to Nashville numbers:



Now you’re free to play it in whatever key you find friendliest to your current abilities.

5. Play Any Song

With practice, you’ll soon find yourself thinking of chords in terms of numbers, almost as an afterthought. When jamming with others, you’ll be able to rattle off the most common chords (usually the 1, 4, and 5) in any key you want to play in, which will help you transpose much faster. So when someone says, “How about a blues in D?” you won’t even have to ask which chords to use.

In addition to moving songs into easier-to-play keys (for example, moving a song in the key of C to D to avoid the F barre chord), you can use transposing to make the song easier to sing by putting it in a better key for your voice. Best yet, you’ll be able to play your favorite songs that have seemed too hard to attempt. Don’t even blink when you find that Green Day’s “Boulevard of Broken Dreams” uses Fm, Ab, Db and Eb. Simply play it with Em, G, C and D. Now try it yourself!

UNLOCK THE KEY
The first step to transposing is figuring out what key the song is in. If you have the sheet music and know how to read it, you can check out the key signature. But even if you don’t know much music theory, there are a few easy ways to find out what key a song is in. These methods aren’t foolproof, but more often than not, they’ll give you the right key.

1. The first chord in the song is usually the same as the key. Take a look at our transcription of “Summertime Blues” on page 46 of the Summer 2007 issue. The first chord is E, so you can guess that the song is in the key of E, and you’d be right.

2. The last chord in the song is usually the same as the key. “Summertime Blues” also ends on the E chord, another indication that it’s in the key of E.

3. The chords used most often are the first, fourth, and fifth chords in the key. Scan through the chords used in the song. It’s full of E, A, and B7 chords. Which key has E, A, and B as the first, fourth, and fifth chords? You guessed it: E.

THE OTHER NUMBER SYSTEM
People versed in formal music theory often use Roman numerals to refer to the scale degree of a chord: I is 1, V is 5, and so on. When using Roman numerals, use capital letters for major chords and lower-case letters for minor chords. For sevenths, ninths and other embellished chords, add the appropriate numeral at the end.

So for example, this progression, in the key of C, could be converted to the Roman numerals shown below.