Every popular retail store that’s part of a big national chain has a familiar feeling all its own. Walking into any Dunkin’ Donuts is like finding yourself in the best-kept, nicest section of a municipal bus station.

It’s never going to feel like home or a fancy law office. You step in, stand in line and squint your eyes at the brown and pink colors lit up by the harshest fluorescent bulbs this side of Bellevue Hospital. You stand there smelling coffee faintly mixed with spray cleaner, and you know exactly what’s offered without glancing up at the menu.

Then you order and take out a donut—and bite into it. You’re feeing better already, and your coffee—while not what is served in Istanbul or Havana—is blazingly hot and warms you like a mother’s hug. “America runs on Dunkin’” proclaims the ads. You’ve run in and out and are on your way feeling that the four bucks was well spent.

That experience—the reliable, utilitarian nature of the environment, product and marketing themes—is the distinctive voice of Dunkin’ Donuts. It comes to you as clearly and consistently as does the voice of your favorite rock star or the President of the United States.

Dunkin’s voice speaks to you harshly in its color scheme but comfortingly in its hot, sweet products. It varies the way a familiar relative’s voice varies—but it is always Dunkin’ just like the familiar relative is always recognizable no matter what the setting.

And that voice is so different from, say, the voice of Starbucks. We don’t need to belabor the point to note that Starbucks’ colors, aroma, seating arrangements, offerings, vocabulary and prices speak to you in an entirely different voice from Dunkin’s.

The Starbucks voice is not the sound of a guy redoing the sheetrock upstairs. It’s the voice of a college-educated, somewhat self-centered person who has a thing about Europe and a preference for Wired Magazine and sugarless gum. How noisy are the Starbucks ads? So understated that you probably can’t recall one.

This comparison is easy. These two coffee chains are polar opposites in tone of voice. But in the digital age defining a strong brand voice that people want to listen to is not easy. It is, however, essential. And our firm helps clients do it.

Claude Singer is an Executive Vice President at Siegelvision.