The Secret to Martin Luther King, Jr.’s Iconic Communication

Tempo in MLKs Speech

Think about the last time you needed a little help getting pumped up for a workout, cheering yourself up after an argument, or winding down after a long day. Did you turn to music?

Many of us have experienced music’s power to sooth or energize — or simply help us “get our minds right.” And, as it turns out, that therapeutic influence is more than just the power of suggestion. Recent studies suggest that music activates the emotional areas of our brain and, according to Dartmouth neuroscientist Thalia Wheatley, “That may explain why it has such power to move us — it’s activating deep-seated brain regions that are used to process emotions.”

Speech Can Affect Audiences in Similar Ways

Given the connection between music and speech — they’re both compositional methods and even share the same areas of the brain — we use automated voice processing to measure the basic characteristics of music such as pitch, amplitude, tone, and tempo, in spoken communication.

What we’ve learned in our research is that, by incorporating the best practices of musical elements in a speech, a presenter can appeal to audience emotions.

One of our favorite ways to demonstrate this connection is with one of history’s most famous speeches — Dr. Martin Luther King Jr.’s “I Have a Dream.”

“I Have a Dream” Demonstrates 3 Musical Techniques that are Vital to Effective Delivery

There’s a lot to admire about Dr. King’s most famous speech but, as far as its connection to music is concerned, three characteristics really stand out.

1.   Tempo

Everyone knows you can’t dance without a beat. And the beat — or tempo — of the song dictates the dance moves.

In order to illustrate the similar effect a speech’s tempo can have on its audience, we analyzed how Dr. Martin Luther King Jr.’s tempo, as measured by words per minute, varied throughout his famous speech.

Tempo in MLK's Speech.pngWe found that the dramatic change in tempo over the course of the 16-minute speech mimics the musical technique of a crescendo, building in intensity as it approaches the most important moment. Dr. King speaks slowly during the first six to seven minutes of the speech, staying between 80 and 90 words per minute while he gives background information. As he gets further into the speech, however, he begins to increase his rate and build more energy.

He begins the famous “I have a dream” section of the speech around 12 minutes in, and builds to this key point by pausing first, then increasing his rate to his maximum tempo as he reaches the climax of the speech — and that climax feels like a powerful chorus of a familiar song, making the audience want to sing along with him.

2.   Melody

Another vocal quality we measure is the harmonics-to-noise ratio, which measures the sonority of a speaker’s voice — how pleasing is it to listen to? Consider Siri, for example. Her harmonics-to-noise ratio is 52% lower than the average female speaker in our database and, while it may be just fine for giving directions, the thought of listening to that robotic tone over conversation in a coffee shop is likely a bit grating.

On the other hand, Dr. King’s voice is 76% more harmonic than the average male voice in our database — and 68% more than the overall average. This indicates a pure, melodic quality that listeners find more authentic and more memorable.

HNR Ration in MLK's Speech.png

It’s important to note that, when the harmonics-to-noise ratio gets too high, a speaker can start to sound overly performative and sing-songy — our favorite example here is the Muppets’ Swedish Chef. But Dr. King’s vocal quality strikes just the right tone to fire up his audience during the March on Washington.

Have you ever had a snatch of melody or a snippet of lyrics stuck in your head? Thanks to its harmonic quality, you may have Dr. King’s voice on repeat next.

3.   Rhythm

How many times have you found yourself tapping out a rhythm on your steering wheel while you were sitting in traffic? That same element that makes music so catchy can have a dramatic impact on a speaker’s performance, as well.

Rhythmic Phrasing in MLK's Speech.pngWe measure the rhythm of a speech by calculating the frequency and variation in the pauses a speaker uses. Too many long pauses tend to make an address feel inauthentic; too few pauses make a speaker seem rushed and nervous.

But Dr. King varies his pauses more effectively than the average speaker in our database — the rhythm of “I Have a Dream” is just right to help audiences absorb and comprehend his message.

Incorporating Musical Techniques into Your Next Presentation

Dr. King is widely considered an amazing orator. Perhaps his experience as a Southern Baptist Preacher gave him a bit of a leg up, but that doesn’t mean his iconic delivery is out of our reach.

In fact, executive communication coach Briar Goldberg says the sound of our communication plays just as big a role in the audience experience as our content and our body language, and the voice is a tool we can all learn to use to make our speeches more effective.

If you’re unsure whether you’re using your voice effectively, Goldberg suggests you start with a few questions: When you speak in public, does each sentence sound different or are you at risk of sounding monotone? How often do you pause? Do you allow the pitch of your voice to inflect naturally?

“You might not need a King-esque melodic crescendo during your next sales meeting but, if you spend a little time thinking about how you use your voice, you can certainly make your presentation more engaging.”

Dr. King’s message is poignant and persuasive on its own, but the musicality makes us feel something in our bones. The mesmerized audience hangs on his every word — they are personally invested and moved to action. His masterful use of musical techniques taps into those emotion areas of the brain that are triggered by music, and as a result, his words will live forever in history.