Rhoticity, Part Two: Symbol Confusion

This post is a part two of an answer to a question posed by Kim Mappleswitch. Part one is here.
As a reminder, Kim writes:

At The High Standards Academy of Dramatic Art (HSADA) we’re required to teach Standard Stage as a basis for learning IPA. I have asked the faculty here how they teach the /ɜ˞/ sound. On one hand – it’s that the tongue tip stays behind the lower teeth and on the other hand it’s that the tongue tip is not on the lower teeth, but rather “floats” because the body of the tongue is slightly retracted. What do you guys think? Rhoticity is a difficult topic and I’d like to have some clarity with this symbol and get some other opinions on how to teach it. In the course packet we are supposed to teach out of it says this is a “pure vowel” but I don’t see how it can be with an r-hook. This is where I’m hitting a wall with this sound.

I dealt with the question of the physicality in the last post. This post will be specifically about the transcription questions around rhoticity (post-vocalic /r/ sounds to you).
This is a vexed area, to say the least.
Most folks in the theatre voice and speech world use ɜ˞ to represent the phoneme in So-Called General American NURSE, just like Kim’s HSADA colleagues. This is a widespread, deeply-rooted convention. It can be found in Kenyon and Knott, Skinner, Patricia Fletcher’s Classically Speaking, Louis Colaianni’s Joy of Phonetics, Paul Meier’s treatment of ‘General American’ and many, many other resources. Even John Wells, in Accents of English, uses /ɜr/ for the ‘GenAm’ phoneme. (Wells’ idiosyncratic use of the ‘all-purpose’ /r/ here, rather than a rhoticity diacritic, is perhaps best left for another discussion. The important point for now is that he concurs with everybody else in using the basic ɜ symbol for the vowel.) ɜ˞, in other words, is a very well-established usage.
This same basic symbol, ɜ, is used to represent the NURSE phoneme in RP, and has been at least since Gimson. It is at least as well-established as the use of ɜ˞ for the equivalent American vowel. This is interesting. Now of course SCGA and RP differ in the all-important aspect of rhoticity. SCGA is rhotic, RP is not. But is this, in fact, the only difference between the two realizations? The widespread practice of using the same basic symbol for both vowels would seem to indicate that we’re talking about the same tongue position, and that the SCGA and RP NURSE vowels differ only in whether or not the sides of the tongue are reaching up for the molars or not. Is this the case? Let’s hold onto that question for a moment while we have a quick look at the IPA vowel chart as it is currently configured.
Since 1993, when the current version of the IPA vowel chart was adopted, the unrounded central vowel situation has been this:

There is one symbol at the same height as Cardinal 2, one symbol at the same height as Cardinal 3, and one symbol halfway in between.
Let’s do a little experiment here. Release your jaw, tongue and lips. Let everything flop open and see if you can let go of any tension or holding in your articulators. Send a little voiced sound through there. Congratulations, you’ve just produced [ə], the only truly relaxed sound possible in human languages. Every other speech sound in existence must necessarily involve some degree of muscular engagement somewhere in the vocal tract. Now say a few NURSE words in a ‘General’ American accent of some kind. “Bernie the pervert learned curses from stern circus girls,” perhaps. Freeze your tongue in the middle of one of those vowels. Feel where it is in your mouth. Compare it to [ə]—relax into [ə] and feel whether your tongue moves or not. Did it raise or lower when it moved from SCGA NURSE to [ə]?
I’m going to guess that it probably lowered. Yes, there’s an extra thing going on—the tongue-bracing action I discussed in the last post. But speak one of these words again in an SCGA accent and hold on the vowel. See whether you can relax the sides of the tongue down while keeping the body in the same position in your mouth. Again, compare it to a [ə]. Dollars to doughnuts it’s higher.
Now, if you’re an RP speaker, or have a killer RP accent (an RP NURSE vowel can be a tricky one for a lot of Americans), speak a few NURSE words in RP. Hold, as before, on the vowel, and feel where your tongue is. Then relax it into an [ə]. Compare and contrast. The result, I’d imagine, is that you discovered your tongue was lower for RP NURSE than for [ə]. So we’ve got three different tongue positions here. Going from lowest (slightly cupped) to highest (slightly arched), we have RP NURSE, then [ə], then SCGA NURSE.
Look again at the chart above. We have three symbols on the IPA vowel chart corresponding more or less perfectly to the tongue heights of these three vowels.
Now, assuming you’re with me so far, please tell me what earthly sense it makes to use the same basic symbol for both RP and SCGA NURSE?
And even more importantly, how can we not expect this to be confusing to students? On the one hand we’re teaching them that the IPA functions on the bedrock principle of one and only one symbol for each unique physical action, and each unique physical action will have only one symbol to represent it. Now we’re telling them that ɜ indicates a vowel lower than [ə], but all you have to do is add a rhoticity diacritic to the basic symbol, ɜ˞, and now we’re describing a vowel that is higher than [ə]. But higher than [ə] is not where ɜ is on the chart! Furthermore, there is a symbol occupying that precise position on the chart, ɘ!
Convention aside, if we were choosing a symbol from scratch to represent a central vowel about the height of Cardinal 2, which one would we choose? The answer is obvious—we’d choose [ɘ]. It’s right there on the chart! The choice for RP NURSE is similarly obvious—we should go with [ɜ]. Again, it’s right there on the chart, an unrounded central vowel about the height of Cardinal 3. That’s the quality we want to describe, and the IPA has provided us with a symbol that lives right there.
So, my preferred usage is:
SCGA NURSE vowel: /ɘ˞/
RP NURSE vowel: /ɜ/
This usage has the advantage of making clear that we’re talking about two completely different tongue positions for the two vowels—one higher than [ə] and one lower. Rhoticity is not the only difference between the two.
Of course, if we teach this, we still have to explain the convention so that students understand what they’re reading when they come across it elsewhere. But it’s far better to go this route, I think, than to just go on pretending that we’re talking about the same thing when we’re really talking about two different things. If one of the main points of teaching phonetics is to allow students to begin to untangle perceptual confusions, then we are certainly not serving that goal if we’re teaching ɜ˞ for American NURSE.
As long as this post has now become, there is still more to say on this subject. In NURSE words, Joe Yankee probably uses some kind of ‘braced’ or ‘molar’ ‘r’, (discussed in the last post), which I’m now choosing to transcribe as [ɘ˞]. But what does he use when a spelled ‘r’ precedes a vowel, as in rutabega?
The answer will have to wait for part three. (Though discussion, as always, is welcome in the comments.)
 
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