A new study published in Royal Society Open Science finds that when a speaker’s full body is visible on video, a deeper-than-average voice heightens perceptions of dominance and physical formidability rather than attractiveness to women. The work, led by James E. Rutter and Lynda G. Boothroyd of Durham University, used paired videos and digitally altered voices to test how voice pitch and resonance influence judgments about men.
The researchers revisit a long-running debate about why male voices deepen during puberty. They note that human voices exhibit marked sexual dimorphism, with puberty-driven changes lowering pitch and altering vocal resonance. These shifts have historically been linked to both mate choice and competition with rivals, a question central to theories of sexual selection.
In earlier work, audio-only studies suggested that lower-pitched voices could be more attractive to women or signal dominance. However, the new study questions whether these effects persist once observers can see a speaker’s physique. The team emphasises that selecting only audio clips might inflate perceptions of size and strength simply because the voice sounds more formidable when heard alone.
In the first experiment, 17 young white men with British accents—aged 19 to 32—stood full-length in identical neutral clothing and counted from one to five while being filmed. Recruited from a rowing club, a university powerlifting society and by word of mouth, their heights ranged from 165.5 to 193.0 centimetres and weights from 46.6 to 128.3 kilograms. An 18th model was excluded due to poor audio quality.
Each voice was digitally adjusted to four pitch levels—very deep (75 Hz), deep (95 Hz), average (115 Hz) and high (135 Hz)—and combined with three resonance levels to produce 12 video variants per man. The researchers then invited 1,466 American adults, aged 18 to 36, to rate or judge a single video from each speaker.
Participants viewed the videos and completed one rating per person: heterosexual women judged attractiveness, while men rated physical strength or fighting ability, and a mixed-gender group assessed social dominance. A separate group watched silent versions of the same clips to assess the influence of visual cues alone.
Across measures, deeper voices did not boost attractiveness once the body was visible. The authors report that a general pattern linking lower frequencies to appeal was driven by a dislike of feminised voices rather than an upward boost for extra-masculine voices. In particular, higher-pitched clips were rated less attractive, and feminised resonance fared poorly, while deeper-than-average voices did not increase attractiveness.
By contrast, lowering pitch and increasing masculine resonance consistently raised ratings of dominance. “When we made their voices higher than average, they received lower ratings for attractiveness, strength, physical formidability, and social dominance,” Rutter explained. “However, when we made their voices deeper than average, they appeared more dominant physically and socially, but not more attractive.”
The researchers were surprised to find that the track of strength rose with deeper voices; a result they describe as unanticipated. “I wanted to run the study because I genuinely had no idea what the results would be, but I think I was most surprised to see that men actually looked stronger when we made their voices deeper,” Rutter said.
Overall, visual appearance outweighed vocal cues in all ratings. Silent videos accounted for roughly 12 to 38 per cent of the variation, while voice changes explained about 1 to 5 per cent. The most pronounced voice effect emerged in social dominance, while physical dominance relied more on what observers could see.
The study also found that the relationship between voice pitch and perceived dominance did not hinge on a participant’s perception of height or weight; interactions with height, weight, or BMI were not statistically significant, suggesting the cues operate largely independently. There was, however, an interaction where raising voice pitch reduced attractiveness more steeply for men already deemed attractive in silent videos.
To probe whether vocal cues distort size estimation, a second experiment recruited 542 men aged 18 to 36 to view the same 204 videos after participants had seen a baseline clip showing a speaker’s actual height and weight. In this phase, 307 US participants guessed weight in pounds, while 235 participants from Germany, Australia and New Zealand guessed height in centimetres. Lowering pitch and masculinising resonance led viewers to estimate the men as heavier, though the effect explained only a small portion of the variance—roughly 0.10 per cent for weight guesses and 0.34 kilograms per 20-Hertz pitch drop, rising to 0.45 kilograms for masculine resonance. Height estimates were not significantly affected.
Rutter emphasised that perceived weight increases may help explain some of the dominance impressions, though he cautioned that the study could not directly link weight perception to dominance judgments. He noted that if extra perceived weight translates to muscle, the modest shifts observed could still be meaningful in competitive contexts, where weight classes often differ by only a few kilograms.
The authors acknowledge several limitations. All raters were from Western, industrialised countries, and the 17 male models included athletes with varying body types, producing a wide BMI range from 17 to 40. The voice samples were brief and highly controlled, consisting of a single, flat count from one to five, yielding only about a second of voiced speech. Wider results might emerge with more natural speech and a broader range of body types.
Rutter suggested that broader studies, including non-Western populations and more ecologically valid vocal samples, could yield stronger effects. He also hinted at future work examining vocal attractiveness in other contexts, such as how a voice might be perceived when someone is under the weather. “I’m looking at vocal attractiveness more in my next paper, which investigates whether people sound more attractive when suffering from a cold,” he said. “Generally perceptions of health and attractiveness are so intertwined, they often feel like the same thing, so I was interested to see why this might not apply to the voice.”
The study is titled Low voice pitch, when accompanied by video, increases perceived dominance but not attractiveness, and was authored by James E. Rutter and Lynda G. Boothroyd.
