Goal: Choose monophthongs
Note: The five-vowel system is a classic option for a good reason.
Tip: Select vowels from opposing areas for maximal distinctions.
Work focus: Organize/Plan/Structure
For the past three days, you have worked on selecting a starting inventory of consonant sounds for your language. Today’s focus shifts to the vowel sounds in your language—specifically, the monophthongs that will be a part of your starting vowel inventory. A monophthong is a vowel produced without movement; its sound is a steady vowel sound. A diphthong, on the other hand, requires movement during production and will be the focus for tomorrow. You can feel the difference if you say “bee,” which has the monophthong [i], and then say the word “bye,” which has the diphthong [ai] (sometimes also transcribed as [aj] or [aɪ]).
As you choose what monophthongs to include, I advise you to keep the following in mind (I will write more about each one after the bulleted list):
- aim for 3-6 monophthongs in your starting inventory
- select sounds from opposing areas of the IPA vowel chart
- avoid “clumping” the vowel sounds together
- sparingly include “opposite rounding” vowels in your starting inventory (if you have any at all)
Aim for 3-6 monophthongs
This guideline is like the consonant range I provided a couple days ago—it is, by no means, meant to be a strict limit but is a starting point for you to work with. Having 3-6 of these vowel sounds will provide a good amount of diversity of sounds in the proto-forms, and they will allow you to select sounds from different areas of the vowel chart for maximal distinction (i.e. so you can actually hear the difference between the vowel sounds when they are produced in context). Some “classic” starting inventories of monophthongs for conlangs (and natlangs) include these sets:
- three-vowel system: [i, u, a]
- four-vowel system: [i, u, a, ǝ]
- five-vowel system: [i, e, u, o, a]
- six-vowel system: [i, e, u, o, a, ǝ]
I call these “classic” because you will find them in many natlangs and conlangs alike.
Select sounds from opposing areas of the IPA vowel chart
As you select monophthongs, choose sounds from different areas of the vowel chart. If you look at the placement of each of the vowel sounds in the “classic” inventories above, you will see that they represent the top, bottom, left, right, and center of the chart. They are spread out. If you have a high front vowel (note that “high” is represented by “close” on some IPA charts), then you should consider having a high back vowel to balance it out. As you move further down the chart into the low vowels (also labeled “open” vowels on some IPA charts), the physical space where those sounds are produced is more limited, so you’re less likely to get front and back vowels at that particular vowel height. You’re more likely to find only one low (or open) vowel in the system.
Avoid “clumping” the vowel sounds together
If you follow the advice above, you’ll naturally avoid clumping vowel sounds. However, if you decide to incorporate more central vowels or vowels outside the “classic” inventories, be sure to look at your system as a whole. If you see you have several vowels all produced in the same area, you may want to reconsider how many of those monophthongs you want to keep. Vowels are the trickiest sounds in language and tend to be more acoustically amorphous than consonant sounds. That is, what is perceived as an [e] in some contexts may be perceived as [ɛ] (or even [æ]!) in others even though the speaker didn’t intend to produce a different sound. A vowel sound can easily slide from an [i] to an [ɪ] without an intended shift in meaning. It’s good to begin with maximally distinct vowel sounds in your proto-inventory, and then, through sound changes, you can introduce more vowel sounds, should you want to expand the system.
Sparingly include “opposite rounding” vowels (if at all) in your starting inventory
On the IPA vowel chart, you will find some sounds written in pairs. When that is the case, the vowel sound on the left is unrounded, which means it is produced with the lips more spread than rounded. The vowel sound on the right is rounded, which means the lips are more rounded than spread when the sound is produced. If you shift from saying [i] to [u] and back again (i.e. make a sound like a siren), you should feel your lips going from an unrounded to a rounded shape. Across natural languages, most vowels are more likely to be unrounded with this major exception: back vowels produced in the mid-to-high ranges (or the mid-to-close ranges) are more likely to be rounded. That is, languages are more likely to have [u] and [o] than they are the unrounded counterparts.
Including vowels with “opposite rounding” means including, for instance, a front rounded vowel, such as the [y] and [ø] sounds found in German words like müde and möchte, respectively, or an unrounded back vowel like [ɯ] or [ɤ].
I advise that you use these sparingly unless you have a solid reason for including these oppositely rounded vowels. For instance, when David and I created Tpaalha, a language for anthropomorphic opossums, during our LangTime livestream, we chose to include the back unrounded vowels in lieu of the more common rounded vowels. We specifically chose to do that to honor the physiology of opossum mouths and the movements we felt would be more natural for them to make. Based on the shape of their mouths, we (and our LangTime viewers) decided it would be too cumbersome for opossums to round their lips to incorporate rounded vowels in their system.