Is there a 'best' key for a male/female song duet

Question

This question may be naive or badly formed, as I'm neither a musician or a songwriter. Please be kind.

I gather that there are certain keys that are easier for ordinary male singers, and others that are easier for females, meaning that the two will not have to stretch outside common ranges.

If that's so, say I'm writing the foundation of a tune, on top of which there will be a melodic line sung by a man and a woman, either in tandem or in alternation.

What would be the best way to write and arrange this so that singers of each sex would find it comfortable?

Can there be a common underlying chord structure that allows the singers to harmonize, rather than sing in the same key in different octaves?

Practical answers appreciated, since most theory is above my head, but if there are good theoretical ones, I'm open.

Answer 1

Let me try to address this exact question as closely to its intent as possible. I like Michael Curtis's simple answer—no, there is no "best key." And yet—we could choose any key, so which should we choose?

Let's assume that you aren't writing for specific individuals, so you don't know their vocal ranges or abilities ahead of time. Let's assume that you're just trying to write something that is comfortably singable by as many people as possible.

Also, you talk about "a melodic line sung by a man and a woman, either in tandem or in alternation." This sounds to me as if you're looking to let the entire melody suit all voice types, so it could be sung in unison, and you're not focusing on "part writing," letting one of the voices be the "main melody" and another be "the harmony," singing other notes that simply sound good along with the melody. So the question becomes "What key should I pick to let as many voices as possible, of any sex, sing this melody comfortably?"

(Note: In unison singing, it's likely that women will be singing an octave higher than men. Look at Michael's image of the vocal ranges: there's only one note in common between soprano and bass, middle C, and that's at their extreme ends—not advisable for untrained voices, and not comfortable. But if you had Fs and Gs in your melody, then the soprano could sing them comfortably above middle C, and the bass could sing them below.)

As I mentioned in a comment, there could be one other thing to think of: convenience for instruments, or for reading the music. Keys with lots of sharps and flats could be hard for an instrumentalist to sight read, or could make the music a bit complicated (double sharps, etc.). It could be smart to consider only keys with up to 3 or 4 flats. This still leaves us with 7 to 9 keys.

Now, here's the unhelpful conclusion: It will depend on the song. First, if you want your song to be as singable as possible by as many people as possible, keep its range as narrow as possible. (Of course, then it's challenging to be expressive and memorable...) Even then, you have to ask yourself "what part of the key" your song's range sits in. For instance: "Mary had a little lamb" has a fairly narrow range; it spans a fifth. If you use solfege syllables, it uses Do, Re, Mi, Fa, and Sol—the "lower half" of the scale. But one could imagine a song that uses the notes Fa, Sol, La, Ti, and Do (the higher "Do"). _{(The "shave and a haircut" tune kind of works, except it lowers the "La".)} It would have the same sized range, but you might have to choose a different key for the second song to "center" its notes in the ideal range. From Michael's image, we've already established that the ideal range would center around the notes F and G. So, for "Mary had a little lamb," the tune starts on the third-highest note of all the notes it uses. If we start on an F# (putting us in the key of D), we'll go down as far as D and up as far as an A. Starting on a G (key of E flat) could also be equally reasonable. In contrast, "Shave and a haircut" starts on its highest note, so an A or B flat might be a good starting note.

Answer 2

I think this is a bit of an "XY Problem". You've asked about key when you would be better off thinking about range. Since you noted you're "neither a musician or a songwriter" this is understandable.

The key, also known as the tonic‡ tells us where the "center" or "focus" of the melody is, but the notes used in the melody can extend nearly arbitrarily up or down from that center.

When a singer asks an accompanist for a reference pitch, it's typically the starting pitch of the song. Although sometimes the starting corresponds to the key, it often doesn't.

As others have said, you can't expect an untrained singer to get much more than an octave range. As others have also said, there is considerable variation between individuals.

Say I decide to limit myself to an octave span from C3 to C4. I could compose a melody in the key of C using that range. I could also compose a melody in any other key using only notes in that same range!

There are numerous online references about typical ranges, but they seem to be weak on statistical rigor and largely neglect untrained singers. An informal review suggests average for men might be about A2 to C4 and women might be A3 to C5.†

You could use this information and try composing two parts that each span about an octave and overlap by about a minor third, e.g. approximately C3-C4 (m) and A3-A4 (f).

You will still need to transpose for some singers.

Also, If you select one male and female singer at random, you might find that transposing your composition to fit one singer's comfortable range will make it difficult or impossible for the other.

‡ If you search, you'll find many good prior questions here about the tonic, for example: How does the tonic establish itself in a melody?

† The first Google hit for "average vocal range for male and female comparison" gives this page which is incorrect in that the frequencies (in Hz) don't align with the pitches (in Scientific Pitch Notation), and each of the pitch ranges given only span a minor third.

Answer 3

The answer is simply, no.

I don't know why there is so much discussion about range. That's a different subject. Even if limited singer range limits available keys, that problem is still a limitation of a singer's range, and will depend on each person.

SATB vocal music needs to contend with four vocal ranges and I've never heard the idea that some keys are off limits or ideal for SATB music. Composers many need to keep the ranges of their part writing under constraint to match voice ranges, but not limit what keys they write in.

A practical approach is to simply write in common keys and keep the melodies within normal vocal ranges.

The other practical approach is to know specifically who the singers will be and sort out their ranges and any key preferences.

You can apply a bit of theory to guide and inform you:

I made a chart of crib notes for vocal ranges...

I based that on ranges from my The Harvard Brief Dictionary of Music.

White note heads are the range mid points, black note heads the extreme ends, and the diamond heads are my addition of simply the the mid-point between middle and high/low extreme for each range.

A common rule of thumb for an easy to sing melody range is one octave. Notice that my diamond head middle portion of the range is a seventh and close to that one octave rule of thumb. You can also see that soprano range is roughly treble clef with no ledger lines and bass range is bass clef with no ledger lines.

Each of the SATB ranges is separated roughly by a fifth.

The middle ranges of each voice overlap the adjacent voices. If you extend a comfortable range from an octave to a tenth, there is even more overlap.

Now, for an example, consider a key of E major and a duet with melodies that range E4 E5 and E3 E4. E4 E5 goes out of the basic range of an alto, but fits right in the middle of the basic soprano range. E3 E4 goes out of the bass range, but fits the tenor range. In this scenario the problem is not the key but knowing what vocal types fit. The duet would be for soprano and tenor.

Keep your melodies on the grand staff with no more than one ledger line above treble or below bass to stay within the ranges of voices.

Keep individual melody parts to a one octave range +/- one step above/below and those parts should fit one of the standard vocal ranges.

Any key should work.

Those are just the guidelines to be aware of. Write the music first (with at least some sensible awareness of vocal ranges) and only worry about adjusting things if you run into an actual problem.

Answer 4

You won't know until you get both together to actually try singing your song. There's no 'magic key' that will be good for any pair of singers.

In fact, your song may even not find suitability for your two designated singers, sadly.

But, by keeping the range of each voice to an octave or just over, there's a good chance at least a couple of keys (close to each other, like E and F) may well suit both.

If you make the range of each voice too wide, someone may well suffer at one end or the other, but by moving keys around, there may still be something suitable.

But, as said earlier, there's no 'magic key'. Sorry!

HOWEVER - there will be A KEY (possibly several) that will suit both the male and female singers. Trouble is, without knowing the range of those singers, along with the range of the song, it's impossible to give a direct answer. So the answer is actually yes, and/or no!

Answer 5

Everybody's voice is different, so there's no way to pick a key and have it be ideal (or even good) for everyone. Songs are very often transposed to fit singers' ranges, so to some degree you can just write it and let the eventual performers deal with picking the right key. However, there are some general tips that you should try to follow.

First, try to keep your melody within about an octave. Untrained singers may be limited to one octave, and singers with a little bit of training may have more range but still have one octave that's the best. You should only expect fully usable two octave ranges from highly trained singers. Study some folk and children's songs, and you'll find that they rarely span more than an octave.

Second, if you're trying to pick a key such that most people can sing it without having to change the key, pick the key such that the melody spans from C to C, or close to it. Which key this is will depend on where the melody sits. Melodies tend to be either authentic, spanning from do to do (e.g., Row Row Row Your Boat) or plagal, spanning from sol to sol (e.g., Happy Birthday). So for an authentic melody, C will work well, and for a plagal melody, F will work well. Or if you happened to write something that spans mi to mi, then A or A-flat would work.

This is because of the way that different voice types, especially when untrained, overlap in range. The classical description of bass range is from E2 to E4, but this is for fully trained voices. An untrained bass's range might look more like G2-C4. For an untrained baritone, it might be A2-D4, and for an untrained tenor, it might be C3-F4. Overlapping these, we see that it might be difficult for some untrained men to sing lower than C3 or higher than C4. For women it's roughly the same, an octave higher. But C to C tends to be possible for most people.

Answer 6

The major key (sorry couldn´t resist) points to consider are the a) ranges of the individual voices b) when they sing together - where they are singing in their respective range 3) how the first two influence the text and meaning intended for the text sung 4) what instruments will be accompanying. The choice of key , aside from range, has a larger influence on the sound of instruments as well as their ability to play a given part with ease, or even at all, than it does for voice where key choice ultimately has more to do with where the given pitches of a song will lie when transposed ( that just means put into a different key).