Voice Characteristics and Selling Effectiveness: What Salespeople’s Voices Reveal About Who Sells More

By Noam Shemla · The Studies

TL;DR An early study that put salespeople’s voices through acoustic analysis. Among 21 direct salespeople, three features of how they spoke were significantly related to how much they sold: how fast they talked, how long they paused, and the shape their pitch traced. Compared with 13 people who did not sell, the salespeople spoke faster and their pitch contours fell more. Yet the customers they were selling to, asked for their impressions, could not tell the better sellers from the rest.

• Paper: Peterson, R. A., Cannito, M. P., & Brown, S. P. (1995). An exploratory investigation of voice characteristics and selling effectiveness. Journal of Personal Selling & Sales Management, 15(1), 1–15.
• Speakers: 21 direct salespeople, and a comparison group of 13 people who did not sell.
• Listeners: 26 women from the product’s target market, described in the paper as housewives, who rated the salespeople from their voices.
• Measures: Acoustic measures of each voice, including speaking rate, average pause length, fundamental-frequency (pitch) contour and loudness variability.
• Outcome: A measure of each salesperson’s output sales performance.
• Headline: Rate, pauses and pitch contour were significantly related to sales; listeners’ impressions were not.
• Access: Subscription-only. This summary uses the published abstract and the way later research has read the paper.

How a salesperson speaks is something every sales manager has an opinion about and almost nobody measures. In 1995, Robert Peterson, a marketing scholar, teamed up with Michael Cannito, a speech scientist, and Steven Brown to measure it: they recorded working salespeople and analysed their voices with the tools phoneticians use.1

What the researchers did

The study has three groups of people in it, and the design is easiest to see as a picture.

What they found

Three of the voice measures were significantly related to sales performance: speaking rate, average pause duration, and the fundamental-frequency contour, the shape the pitch traces over a phrase. Later research reads the speaking-rate result as faster speech going with better selling, and cites the study alongside other work showing that a quicker pace signals confidence and helps persuasion.2 Loudness variability, how much the volume moved around, was not related to sales.3

The comparison group gives the second result. Set against 13 people who did not sell for a living, the salespeople spoke more rapidly and produced pitch contours that fell more.

The third result is the strangest. The 26 listeners, drawn from the people the product was sold to, could hear the differences in speed between the salespeople. But their impressions of the salespeople were not related to the voice measures, and not related to how much each salesperson sold.

What was measured, and what it was linked to

What the measures mean

The three features that mattered are simple to define, even if measuring them well takes care. Speaking rate is how much speech fits into the time spent speaking, usually counted in syllables so that long and short words weigh the same. Pause length is the average silence between stretches of speech. And a pitch contour is usually summarised by how far the pitch moves over the last part of a phrase, in semitones, the units of a musical scale, because the ear hears pitch in ratios rather than in hertz.

A falling contour is the sound of a statement that has finished. A rising one, at the end of something that is not a question, can make a statement sound like a request for approval. The salespeople’s contours fell more than those of people who did not sell, which fits the idea that they sounded more like people stating things.

Has it held up?

The study was small, but the direction of later work is consistent with it.

In three experiments, Thomas Vaughan-Johnston and colleagues found that ending sentences on a falling rather than a rising intonation signals that the speaker is confident, and that under moderate levels of attention it made listeners process the message more, which helped strong arguments more than weak ones.2 So a falling contour is not a trick that works regardless of content; it makes people listen to what you said.

At a much larger scale, Haifeng Xu and colleagues analysed more than 8,000 real telephone sales calls in China, plus an experiment, and found that the brightness and loudness of salespeople’s voices predicted whether new customers bought and how quickly. The features that helped with new customers were not the same as the ones that helped with existing customers, which is a reminder that no single “selling voice” exists.3

What this study cannot tell you

• 21 salespeople is a very small sample, and the authors called the study exploratory.
• It is correlational. Faster, more fluent speech may come with experience, product knowledge or confidence, any of which could drive sales on its own.
• The listeners’ result cuts both ways. Their impressions did not track sales, so the study cannot say how voice might influence buying, only that some features went together with it.
• We could not read the paper. It is subscription-only, so this summary reports what the abstract states and what later research says about it, and redraws none of its tables.

What a speaker can take from it

Two things in this study are directly trainable: pace and the ends of your sentences.

Pace. On the usual reading of the result, the better sellers spoke faster, and people who sell for a living spoke faster than people who do not. Fluent pace usually comes from knowing your material well enough not to search for words, which is exactly what rehearsal builds.

Endings. Let statements land. Say the last word of a claim on a pitch that goes down, not up; that is the falling contour the salespeople produced more of. It is one of the easiest habits to hear in a recording of yourself and one of the quickest to change.

The listeners’ result is worth keeping in mind too. What customers said they thought of a voice was a poor guide to how well it sold. Measuring your delivery tells you more than asking how it came across.

This article summarises a subscription-only paper from its published abstract. Which features were related to sales, and how salespeople differed from non-salespeople, are from the abstract; the loudness result and the reading of speaking rate come from later papers that cite it. The equations are standard definitions, not the paper’s own.

Measured

• Acoustic features of recorded salespeople and non-salespeople
• Each salesperson’s output sales performance
• Listeners’ impressions of the salespeople from their voices

Inferred, not measured

• That faster speech went with more sales, as later research reads the result; the abstract does not state the direction
• Any causal effect of voice on sales: the study is correlational

References

1. Peterson, R. A., Cannito, M. P., & Brown, S. P. (1995). An exploratory investigation of voice characteristics and selling effectiveness. Journal of Personal Selling & Sales Management, 15(1), 1–15. https://doi.org/10.1080/08853134.1995.10754008
2. Vaughan-Johnston, T. I., Guyer, J. J., Fabrigar, L. R., Lamprinakos, G., & Briñol, P. (2026). Falling vocal intonation signals speaker confidence and conditionally boosts persuasion. Personality and Social Psychology Bulletin, 52(1), 3–21. https://doi.org/10.1177/01461672241262180
3. Xu, H., Ding, Y., Ding, Y., Zhang, Q., & Zhang, C. (2026). Whispers in your mind: the role of voice features in customer acquisition and retention. Journal of Marketing, 90(1), 29–50. https://doi.org/10.1177/00222429251328293