Just from hearing someone speak, not reliably. Perhaps if someone speaks with a naturally booming tone in a low register it's a good guess that they're a lower voice type, but the opposite isn't true at all--just because someone speaks with a higher or lighter tone doesn't mean that they're a higher voice type.
Determining someone's vocal classification takes time and only makes sense if they have some vocal training. Vocal classification is somewhat about range, but is more about tessitura, which is where their voice sits the most naturally. With men, range and tessitura tend to follow each other, but it's really common to find women who are capable of producing notes far outside their tessitura, but which don't sound very good. Really working out where someone is strongest takes time with a qualified voice teacher.
In another comment, you said:
> this choir only has, in theory, four voice types: soprano, alto, tenor and bass, so I suspect that some might be in the middle and perhaps the basses are actually baritone, since basses are rare.
Yes, this is a common problem in choirs. The distribution of voices follows a bell curve, and most people are in the middle. Most men are baritones, and most women are mezzo-sopranos. Choirs are typically divided into soprano, alto, tenor, and bass, which on the surface might seem to force all of those middle voices to sing out of range. However, upon further inspection, most choir music doesn't push the extremes too hard, and each of the four sections are usually divided in two. Soprano 1 will be true sopranos, soprano 2 will be higher mezzos, alto 1 will be lower mezzos, alto 2 will be true contraltos; and similar for the men. Or at least mostly that way--it's also okay if an individual is a little out of their tessitura, it won't hurt anything.
Also remember that people's voices are a continuous spectrum and don't neatly fall into any category you might define, and people's voices change over time. And then there's also genre-specific concerns and conventions.
maestro2005 t1_je5xrln wrote
Reply to Can you tell someone's voice range only by hearing them sing/talk? by duchesskitten6
Just from hearing someone speak, not reliably. Perhaps if someone speaks with a naturally booming tone in a low register it's a good guess that they're a lower voice type, but the opposite isn't true at all--just because someone speaks with a higher or lighter tone doesn't mean that they're a higher voice type.
Determining someone's vocal classification takes time and only makes sense if they have some vocal training. Vocal classification is somewhat about range, but is more about tessitura, which is where their voice sits the most naturally. With men, range and tessitura tend to follow each other, but it's really common to find women who are capable of producing notes far outside their tessitura, but which don't sound very good. Really working out where someone is strongest takes time with a qualified voice teacher.
In another comment, you said:
> this choir only has, in theory, four voice types: soprano, alto, tenor and bass, so I suspect that some might be in the middle and perhaps the basses are actually baritone, since basses are rare.
Yes, this is a common problem in choirs. The distribution of voices follows a bell curve, and most people are in the middle. Most men are baritones, and most women are mezzo-sopranos. Choirs are typically divided into soprano, alto, tenor, and bass, which on the surface might seem to force all of those middle voices to sing out of range. However, upon further inspection, most choir music doesn't push the extremes too hard, and each of the four sections are usually divided in two. Soprano 1 will be true sopranos, soprano 2 will be higher mezzos, alto 1 will be lower mezzos, alto 2 will be true contraltos; and similar for the men. Or at least mostly that way--it's also okay if an individual is a little out of their tessitura, it won't hurt anything.
Also remember that people's voices are a continuous spectrum and don't neatly fall into any category you might define, and people's voices change over time. And then there's also genre-specific concerns and conventions.