Unless you've been living in a cave, you've heard of Steven Slater--the now-famous Jet Blue flight attendant who recently quit his job by giving a verbal lashing to a passenger over the aircrafts's PA system. He then deployed the emergency slide, grabbed a beer from the bevvy cart, and slid to freedom (until he was arrested shortly thereafter).
I was listening to a podcast the other day, and someone said that one of the reasons this story has captured the imagination of people everywhere (other than the fact that 95% of us wish we had the nuts to deploy our own escape slides) is that the visual of it is so good. That struck me as spot on. I have not seen, nor been able to find, an actual image of Slater descending the big yellow inflatable slide, beer in hand, but ten years from now I'll remember that story as if I'd actually seen a movie of it.
I think my favorite visual description ever is in Jitterbug Perfume, by Tom Robbins. He describes two women walking up a stairway: "Their backsides swung like mandolins on a gypsy wagon wall." Such a simple set of words, yet I can picture it exactly. The shape of mandolins. The way they sway in approximate unison, bouncing slightly. The fact that this is a gypsy wagon adds a certain attitude to the way they move. It's what you might call theater of the mind.
When a radio spot is visual, you'll often hear people say that. Theater of the mind. The spot conjures a clear image in the mind of the listener. All radio should do this. But really, all writing should do this. Most people remember visually (ever hear of the memorization trick where you construct a house in your mind, then assign the things you need to memorize to parts of the house?--you're building a visual to help you remember). So anytime you can create a strong visual, you should.
But as we've seen, not all visuals are literally visual. And sometimes they're better that way.
The other day, a student was showing me the concept for an ad in which a young kid was standing over a pride of lions feasting on their kill in the middle of the Serengeti. I asked him to see what happened if he tried to tell the same story with a headline. I don't know if it'll be any better, but the thing I've found is that often, especially when an image is a little ridiculous, a headline is a better visual than a visual would be. That is, letting the audience imagine an image is often more powerful than just showing it.
Consider this ad from Carmichael Lynch for Motorola walkie talkies:
What are you seeing? The visual is some kids waving from a boat. But what we're all really seeing is poor Paps with his head jammed in the pump. I don't even know what a bilge pump looks like, but the image I have in my head is pretty damn funny. Much funnier than if they'd just shown Grandpa stuck in a pump.
When you let the audience imagine the scene, you're involving them. That's something you always want to do. Of course, to do it right, your language had better be spot on. Your words need to be tangible. They need to be specific. "Bilge pump" makes the Carmichael Lynch ad. And your words need to be accurate. Even though I have never seen mandolins swinging on a gypsy wagon wall, I know that I am seeing the exact same bottoms in my head that Tom Robbins saw in his head when he wrote that line.