…or, why not to blow your fourth too early.
I’m sure a lot has been written about the I, IV and V chords but I have to start at the beginning. They’re the bases of most blues, country and pop songs and in the key of C would be the C, F and G chords. However, thinking in numbers removes the key from the discussion allowing the chords to then be reapplied to any key as necessary. For example, the I, IV and V chords in the key of Bb are Bb, Eb and F. Consult your fingers for assistance, that’s what I did.
The I chord is the home chord and you’ll need a pretty good reason not to start and end with this one. The V chord pairs nicely with the I chord and can be safely vamped without changing the direction of a song. More commonly though it’s thought of as the chord with the most tension and drives to resolve to the I chord so a vamp between the I and V is pleasing as it’s continuous tension and resolve; like breathing in and out. In the key of C the V chord would contain at least a G, B and D. The B resolves up to a C (the closest half step), the D could go either way to an E or C and the G chords is fine where as it’s a shared note between the I and V chord. We now have a chord of C, E and G which makes up the C major chord, or the I chord, which is where the G chord naturally wants to go. Try singing Happy Birthday in a crowded room and stop dead on the last “to”, omitting the final “you”. While they might not understand why, there will be an uncontrollable urge to say the final “you” as without it there was no resolution of the V chord. Here’s a quick chart that may help put context to the letters above.
_______________________________________ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |_| |_| | |_| |_| |_| | |_| |_| | | | | | | | | ->| |<->| | | | | | | G | | B | C | D | E | |___|___|___|___|___|___|___|___|___|___|

The IV chord is the real game-changer in the first group of three. While some polkas may be content in sticking with the I and V, most songs want to branch out and see the world. Think of the I chord as your bed and the V chord as your workplace. Your day is complete when both are accomplished, but if it was your response to what you did today it would come across as boring and off-putting. The IV chord is the nugget of news that captures people’s attention. It’s the accident you witness on the way to work that people want to hear about. It’s the vacation you took to break up the monotony of days. While there are dozens of chords to chose from as you venture outside of the I and V, the IV chord is the must-see stop along the way. It’s also very versatile serving as a pivot point asking “where do we go next?”. It can act as a bridge to the V or return safely to the I as is common in many verses. If the rebel in you gritted your teeth at my comment about ending on the I chord you’ll be relieved to hear that ending on the IV chord can create that dissonance without discomfort. The ending of Freeze-frame is an example of this.
Does this information about these 3 basic chords help to play simple songs by ear? Not entirely, but if you understand how and why each chord works it helps to take the guessing game out of it. In the end it’s practice that removes this guessing game and I’ll start with a few examples that highlight the power of the IV chord.
The first example is “Birthday” by the Beatles and highlights a simple and bluesy I-IV-V chord progression. The IV chord is introduced rather quickly as is common in most blues tunes, and many rock songs. Sing it from the lyrics below, or follow along with the video. The requisite I and V chords are present and the tune starts and ends with the I with proper resolution at the end from the V to the I. The IV chord adds the flavor here and of all chords it’s is the one that could be omitted, though the tune would lose part of what makes it interesting.
Birthday! (I) You say it's your birthday It's my birthday too yeah (IV) They say it's your birthday (I) We're gonna have a good time (V) I'm glad it's your birthday (I) Happy birthday to you
The moment a IV chord is used the adventure begins, though that feeling of exploration is lost once the IV chord is heard and cannot be returned in that phrase or passage. Not blowing your 4th in the beginning has its advantages and highlights how the IV chord gives a song direction. The simple tune “Oh Susanna” is a great example of this. In the example below, sing the lines up to the bolded “Oh! Susanna”, or the first 4 lines. If the song ended there it would sound simple, yet complete. However, the IV is introduced to bring new life to the tune. It’s the scenic stop along your commute that makes your day worthwhile.
Oh! Susanna (I) I came from Alabama, Wid a banjo on my (V) knee, (I) I'm gwyne to Louisiana, My true love for to (V) see. (I) It rain'd all night the day I left, The weather it was (V) dry, (I) The sun so hot I froze to death; (V) Susanna, don't you (I) cry. (IV) Oh! Susanna, Oh (I) don't you cry for (V) me, cos' I've (I) come from Alabama, Wid my (V) banjo on my (I) knee
The final example (from Evita [2:36 in]) is a more complex song that still sticks exclusively to the 3 basic chords. It’s a fun mental exercise to anticipate the IV or V as they interplay with the I. The first 3 instances of the IV chord pass quickly and don’t give you that true IV feel. I always think of the song Footloose (or [IV]Foot[I]loose), where the IV chord quickly moves to the I though not due to any inherent tension. The true IV feel is present after the “swallowed up” line bolded below. Listen the recording and hear the different feeling the 4th IV chord has over the previous 3.
Eva, Beware of the City (I) Eva, be(IV)ware of the (I) city, It's (IV) hungry and (I) cold, (IV) can't be cont(I)rolled, it is (V) mad. (I) Those who are (V) fools are (I) swallowed up (IV) whole, and (I) those who are (V) not become (I) what they should (IV) not become, (I) changed - in (V) short they go (I) bad.
While a simple 3-chord song sounds simple, it takes practice and a trained ear to always hear which of the 3 are being played.
