Solution to Last Month's Mystery Spectrogram

Solution for August 2006

labeled spectrogram
"Most are perfectly capable."

Lower-case M
[m], IPA 114
We start with a clear sonorant consonant of some kind, fully voiced, nicely striated, and with nice clear resonances all the way up. The formants are flat, and there's a nice clear zero about 750 Hz, both of which suggest a nasal. The pole (formant) around 1100 Hz suggests a bilabial (at least for my voice--an alveolar nasal usually has a pole somewhat higher, closer to 1400 or 1500 Hz, and a velar nasal a) wouldn't be initial in an English utterance and b) would have more evidence of velar transitions in the following vowel.

Lower-case O + Upsilon
[nʊ], IPA 307 + 321
I love the overlap between this and the following consonant, but whatever. F1 is at about 500 Hz or just higher. F2 is up around 1100 Hz or thereabouts. F3 is high for some reason. But since this is a vowel we're not going to worry about F3. Just put it out of your mind. Don't let it consume you for twenty minutes like I just did. So we've got the F1 of a mid-ish vowel, and the F2 of something fairly back and/or round. The F1 and F2 seem to move downward slightly (hence the transcription as a diphthong) but you'll notice that the upper frequencies are taken over by the incipient sibilant noise coming up. Gestural overlap? Spreading? Whatever. The illusion of segments. Moving on.

Lower-case S
[s], IPA 132
Well, since it's September, we'll review. From about 350 to almost 500 msec. This is a fricative (random, snowy 'noise'). It's voiceless (no striations or energy in the low-frequency 'voicing bar'). And the noise is in a single, very broad band (unfiltered by a lot of vocal tract resonances) which suggests that it's relatively forward in the vocal tract. It's very loud (and broad band) which suggests sibilance, and centered in the very high frequencies, which suggests alveolar (the postalveolar sibilant is usually centered in the F2/F3 range rahter than above the F4 range). So this must be an [s]. [s] is your friend, spectrographically speaking.

Lower-case T
[t], IPA 103
Our first real plosive. From about 475 msec to the release burst at about 525 msec there's a gap in the spectrogram, indicating no airflow, no resonance, no voicing, squat. It's got a short VOT (not even 25 msec) so it's unaspirated. Voiceless goes without saying, right? (Study question: Why?) The F2 transition starts at about 1600 Hz and falls, the F3 transition starts around 2400 Hz and again falls. So we have 'uppy' pointing transitions (pointing into the gap, that is) and so this is probably an alveolar. The noise in the VOT is a little low (we'd like to see more [s]-looking release noise following a [t], but there's a coarticulatory thing going on....

Schwa + Turned R
[əɹ], IPA 322 + 151
Okay, I've transcribed a diphthong here because there was just no place to segment. Sorry. I've also used a deceptive sequence of symbols--for a lot of people, the sequence schwa-r is a shorthand for the symbol schwa-r (i.e. [ɚ] IPA 327, for which I always use turned-r with the syllabicity diacritic, i.e. [ɹ̩].) But here we have something that looks and sounds like a diphthong. So I've transcribed it as such. F1 is in the mid-region. F2 is neutral (and falling). F3 is sort of neutral but also falling. The end of the F3 fall is way below 1800 Hz, which accounts for the F2 fall as well--that is, that's rhoticity, i.e. approximant /r/ in North American English. But there's a non-rhotic vowel in front of it. So it's a diphthong.

Lower-case P + Right Superscript H
[p ʰ], IPA 101 + 404
Another gap. This one is long,and that might mean there's a sequence here. Or it might mean it's initial in some domain. The transitions into it are a bit difficult to interpret, since the F2 and F3 are pulled down so far by the /r/. But if it weren't for the /r/, these would look bilabial. I mean, they point down. The release at about 700 msec has a lot of noise in the very low frequencies. The transient seems to go all the way up, but it's neither 'sharp' (typical of especially alveolar stops--especially if accompanied by sibilant noise, which this isn't) nor 'doubled' (more typical of velars, especially if accompanied by 'pinch). Well, F2 and F3 are close together, but that could just be because F3 is so low in the following vowel. That's also a reason why the previous /r/ doesn't transition anywhere else. On the other hand, both of those suggest that there's no coronal action in this consonant, which leads us back to considering bilabials and velars. So if we look at the transitions in the aspiration noise, it looks to me like F2 and F3 both pont down into the gap (that is, rise as they move into the vowel), and so the transitions look bilabial. And voiceless, of course, and the loooong VOT can't be anything but aspirated.

Turned R + Syllabicity Mark
[ɹ̩], IPA 151 + 431

See, this is a syllabic /r/. It's not a vowel like schwa 'combined' with some diphthongy rhoticity. It's just a vowel. F1 is mid-ish, F2 is as neutral as it can get, considering the F3 is around 1600 or 1700 Hz. An F3 that low can only be an /r/.

Lower-case F
[f], IPA 128
What we have here is another voiceless fricative. Now take a moment and compare it to the previous [s]. Broad band noise but not of sibilant amplitude. So probably fairly far forward in the vocal tract. Given that this is English this means labiodental or (inter)dental. Any other clues? The F2 in the preceding /r/ seems to transition downward, just a tad, while the F3 is rising, slightly. The only reason for the F2 to not be transitioning in the same direction as the F3 is if it's a labial transition. The transitions on the other side of the fricative all point down (that is, rise into the vowel, which also makes this look bilabial. Now, we might discount the F3 transition as just 'rising' from the low position for the /r/. But the F2 transition(s) still look(s) labial. Vaguely. So probably [f]. The double clunky thing at the onset of the vowel is probably just a clunky thing.

Barred I
[ɨ], IPA 317
Absurdly short vowel. Reduced. Ignore it. Well, don't ignore it, but don't waste any time trying to identify it. Move on.

Lower-case K
[k], IPA 109
Another long gap, but now there's another double clunky thing at about 1100 msec, in the F3/F4 range. Not much of a cue, but double burstiness is sometimes indicative of a velar release. Then again, there's another double-bursty-looking thing at 1150 msec (or so) which I'm going to claim is a red herring (or rather, that the usual explanation for velic double-bursting doesn't account for the other double clunk (either of them), but my explanation will. Anyway, that's really the only clue that there's something else going on here, or that it's a velar release into another plosive. So if you caught it great, if you didn't, you'll have to insert it in through lexical identification later.

Lower-case T
[t], IPA 103
The release here is good and sharp. It looks doubled, but I think most of the energy is in the F3, rather than in a pinched F2/F3 combination. F2 seems to start at about 1500 Hz. So what's going on? I'm going to suggest the release at 1150 msec is coronal, and that the double clunkiness we see is the result of ...

Tilde L (Dark L)
[ɫ], IPA 209
... lateral release. I was being persnickety with the half-under-ring diacrhitic but the point is that there's dark /l/ here, partially (or fully) devoiced by the aspiration following the /t/. The lowness of the F2 transition (relative to the expected frequency of 1700-1800 Hz) is compatible with rounding, but I'm going to suggest that it's there result of velarization of the lateral. The second clunk is the other side of the lateral releasing. So my story on double clunks is that they involve two sides opening at different moments. So velars and laterally released [t] is most likely to have a double burst. The standard story is that the long closure associated with velars (and dentals) causes a high-velocity airflow on release, and a Bernoulli 'clunk' immediately after release. I think I'm right, but I'm apparently the only one. And sometimes a clunk is just a clunk. The vocal tract is a juicy place, after all.

Lower-case I
[i], IPA 301
So after all that, we end up with an F2 up above 2000 Hz (way up above) and an F1 which is quite a bit lower than the mid-ish F1s we've been seeing. So this is a highish vowel, amazingly front. /i/ or /e/. In this case [i]. Trust me.

Lower-case K + Right Superscript H
[kʰ], IPA 109 + 404
Ah, another gap. I hope you noticed the subtle velar pinch in the preceding transitions. Also the double burst. And the long aspiration noise, concentrated in the F1/F3 region. All classic velar signs.

Lower-case E
[e], IPA 302
Now this is a flat /e/. Not diphthongy. F1 is mid or just low, F2 is around 2000 Hz and relatively stable. Not obviously a diphthong. So there.

Lower-case P
[p], IPA 101
A gap of about 100 msec. Withs ome perseverative voicing, but not enough to worry about. The burst is not amazingly sharp, and it seems to be loudest in the low frequencies. If I work hard enough I can convince myself that the F2 and F3 transitions into this gap are bilabial, but they're not obviously sow on the other side. At least they're not obviously anything else....

Schwa
[ə], IPA 322
Another absurdly short vowel, mostly transition, so all it reduced and move on.

Lower-case B
[b], IPA 102
Well here's gap. Notice that the perseverative voicing here is more 'voiced'. Probably meaningful, although there's no guarantee. THe transitions into this look bilabial, at least the F2 does. The F3 and F4 transitions out of this gap and into the following vowel are also suggesting bilabial more than anything else. So potentially voiced and bilabial.

Schwa
[ə], IPA 322
I hear a vowel here, so I guess it's a schwa. But it's really so totally coarticulated with all but the contact-part of the following lateral, that I can't really blame you for wondering what the heck I'm talking about.

Tilde L (Dark L)
[ɫ], IPA 209
Okay, so here's the trick. THe formants, such as they are, indicate a mid-ish vowel (neutral F1), and a very back or round tongue body F2 well below 1000 Hz. Ideally we'd like to see F3 (or at least F4) rise to above neutral for a lateral, but no such luck. But it can't be an /r/ with an F3 like that, and it certainly can't be a /j/ with an F2 like that. So that leaves the lateral and the labial-velar. So which is more likely to a) follow schwa and b) form a word with the preceding. But you can see how dark /l/s and /w/ or /u/ shaped vowels can resemble one another....