Solution to Last Month's Mystery Spectrogram

Solution for December 2007

labeled spectrogram
"You don't want a cheap substitute."

Technically, it's January. So even though this is the solution to December 2006, I'm embarking on my January 2007 policy of no longer marking up IPA characters as being in a special font. From here on out, you must view my page(s) in a IPA-enabled Unicode-compliant font. I recommend Gentium from among the freeware available fonts. My style sheet automagically prefers Gentium if you have it loaded on your system. See my list of supported fonts for more information.

Lower-case J
[j], IPA 153
Starting at about 100 msec is a period of voicing. It's sort of weak, in that it gets a lot stronger in the following vowel, and there's no evidence of energy between the the voicing bar/F1 or whatever it is and the F2, which is up above 2000 Hz. So while voiced and sonorant (i.e. with resonances, indicating an open vocal tract), it's not a vowel. So it has to be a nasal or an approximant of some kind. Could be a nasal (sonorant, overall weak amplitude, and an apparent zero above F1), that doesn't jive with the F2. More than anything else, this looks like a consonant version of an high front vowel [i]. Can anyone say palatal approximant?

Barred I
[ɨ], IPA 317
Well, the F1/voicing bar whatever thingy is stronger here (from about 150 msec to about 225 msec), and the striations between F1 and F2 come in, but it's still weak, compared with vowels coming later on. Weakness, in vowel amplitude, is a correlate of lack-of-stress, so this is probably a reduced vowel. F2 is closer to F3, so following Keating et al (1994), it's transcribed as barred-i.

Lower-case D
[d], IPA 104
Well, there's some weak voicing down at the bottom, but absolutely nothing above that, and just before 300 msec there's a nice sharp burst. The burst indicates that this has to be a plosive, since only an obstruent has pressure that releases in a burst like that. The F3 is not telling us a great deal. The F2 transitions are headed toward that 'around 1700 Hz' area often associated with alveolar transitions. So on the balance, this is probably an alveolar, although I could entertain an argument for a front velar. Although the burst is a little 'sharp' for that...

Lower-case O + Upsilon
[oʊ], IPA 307 + 321
So, abstracting away from the transitions from the plosive, the F1 seems to hit a 'moment' at about 350 msec around 600 Hz, and then starts to head back down. Maxima/minima 'turning point' 'moments' like that usually indicate a 'target' of some kind has been reached (or undershot) between other targets, so this vowel starts either lower-mid or low, and then moves toward someplace higher in the space. The F2 doesn't hit its 'moment' at the same time, so chances are this is one coordinated movement rather than two distinct targets. The F2 'moment' is a low just around 900 Hz (very back and or round) at a 'moment' when the F2 seems to straighten out. So this moment is mid-to-higher-mid and backish/roundish. So going from somewhere sort of back and lower-mid (at the first F1 'moment') to higher and backer/round (at the F2 'moment') is something like a backish mid, tense vowel, diphthongized to something higher and rounder (or backer). Or [nʊ].

Lower-case N
[n], IPA 116
Well, there's something going on between the time the resonances cut off (at about 450 msec) and the bursty thing (maybe it's just a pulse) at 500 msec. There's a sharp reduction in voicing amplitude and resonance, but there's some evidence of open-ness (in the vocal-tract resonating sense) in the F3(?) range above 2000 Hz. It's weak but it's there. And not much else until you get well above 4000 Hz, and there's something noisy happening in the low frequencies. So what is this? Well, it's open so we're talking vowel, approximant, or nasal. The fact that the F3 seems to drop into it while the F2 seems to rise would suggest velar pinch. Which we'd be thrilled about, because the confirming evidence is the apparent double-burst at 500 msec, right there in the F2/F3 pinch range, where we'd expect a velar release to be. So we'd conclude that we're looking at a velar nasal followed by a velar plosive release. Homorganicity and all that. But this would be a red herring, because there's no evidence of velar transition after the releasey thing. So we'll have to com eup with another hypothesis. Which would either be [mb] or [nd]. And there's not a lot to tell us that's unequivocal.

Lower-case T
[t], IPA 103
So on the end of that nasal thingy is a burst, is a stop homorganic (same place of articulation) with (to?) the nasal. Transcribed here as voiceless, because I convinced myself there was a short VOT, but now I'm not sure. It's ambiguous, as I said before, because a) the burst is double, and in the right range, but the transitions don't match up with anything velar. The F3 isn't doing much, and the F2 is so co-produced with the following, um, thing, that it's not telling us much. So in the end, we'll rely on lexical access to fill this one in later.

Lower Case W
[w], IPA 170
So going from that moment of burst to about 550 msec, there's increasing amplitude and sonority. So I call that a thing. Weaker than a vowel, probably an approximant, since in all other respects it's continuous with the vowel. The F1 is low. The F2 is low. The F3 is just sitting there. So we've got something very back/round and close.

Script A
[ɑ], IPA 305
Well the F1 and F2 are pretty much all transition here, but there are some things to be gleaned. Note that the F1 rises from its pushed-down-by-the-F2 position at the start to about 700 Hz around 675 msec. ANd then it levels off, or even drops a little. So there's something lower-mid or low that it's heading toward. The F2 is still low there, so it's possibly still being pushed down a little, but the point is that there's a moment in there we need to pay attention to. And at that moment, the F1 indicates something a fairly low vowel, and about as back as it can get.

Lower-case N
[n], IPA 116
And now there's another of these things. This one is less ambiguous, though not by much. F2 is at least rising so it can't be labial and the F3 is just sitting there, so this is unlikely to be velar. So this is probably alveolar. There's stuff going on that looks a little like voicing at the bottom, but otherwise this looks like a plosive, down to the sharp, alveolar-looking release. So probably a nasal, with a following plosive...

Lower-case T
[t], IPA 103
... homorganic of course. The release is nice and alveolar-looking, with it's sharp onset and high-frequency-tilted noise. Finally.

Barred I
[ɨ], IPA 317
And here's another shortish, weakish vowel (hey, at least it looks like a vowel).

Lower-case T
[t], IPA 103
So around 825-850 msec or so, everything kind of stops. No voicing, no energy, no noise, anywhere. There's no closure transient, but then how often are we lucky enough to get one of those. The release happens at about 900 msec, and while weak is very sharp and in that high-frequency alveolar-looking range again.

Esh
[ʃ], IPA 134
This noise is interesting, since it's very [s]-shaped. It's a single, broad band, centered around 3000-3500 Hz, depending on where exactly you look. That's a little low for an [s], but whatever. The real give-away is the fact that the noise stops dead around 1800 Hz, that is just below F2. Which is almost always a classic indicator of a postalveolar fricative, i.e. [ʃ].

Lower-case I
[i], IPA 301
So for almost 100 msec, we've got a fairly flat, stable vowel. Yay. F1 is very low, F2 is very high (2100 Hz or over!), which can really only be an [i]. As high (low F1) and as front (high F2) as can be.

Lower-case P
[p], IPA 101
Another gap, indicating another plosive. Transition wise, there's not a lot going on. F3 is coming down just a little, and I can convince myself that F2 is as well, although that may just be me and my imagination running wild (armed with the knowledge of what's really going on here as well...). The release burst is again sort of sharp and tilted to the high frequencies, but that doesn't jive with the apparently labial looking transitions. Hmm. I'm trying hard to force this to look bilabial, but except for making a big deal of the low-frequency components of the release transient (which aren't really missing in the previous alveolar releases, so it would be a lot of handwaving) I'm not having much luck.

Lower-case S
[s], IPA 132
On the other hand, the [s]-shaped tilt to the burst noise might be influenced by the high-frequency tilt to thise noise. Note that it isn't completely contiguous with the burst, which may suggest that this isn't just a [ts] kind of transition. Anyway, note the off-the-top center of this noise. That's more typical of an [s] than the [ʃ] we saw earlier.

Turned A
[ɐ], IPA 324
I'm sick of using turned V [ʌ] (which the IPA defines as Cardinal 14, the unrounded version of open-o) for this vowel. The vowels traditionally transcribed as turned-v in English are historically related to short o (and short u), but in my dialect and in Canadian English there's nothing back about it. The turned (print) a symbol [ɐ] represents (in strict IPA style) a central vowel of indeterminate height between lower-mid and low. So it is with this vowel. The F1 is a little higher than 500 Hz, so vaguely lower-mid. The F2 is a little low of central, so vaguely back, but not at all round. So take your pick. I think the F2 is being pulled down a little here by the following consonant, but that's just me. If you don't like it, keep using turned-v, but you're unlikely to see it again here.

Lower-case B
[b], IPA 102
F2 and F4 are pointed down. F3 may be or may not be. But F2 and F4 both look labial. The gap is clearly voiced (look at those nice clear striations), so we're talking [b].

Lower-case S
[s], IPA 132
Stronger than the last one, but clearly high-frequency and broad band, and even though the lower frequencies are attenuated, there's not the abrupt cut-off at F2 we associated with postalveolars.

Lower-case T
[t], IPA 103
Shortish gap here, with a sharp release (gosh, it looks like the labial release from before, huh?) but the noise in the short VOT is [s]-shaped, which we really only ever see with alveolar releases.

Barred I
[ɨ], IPA 317
Shortest vowel of the spectrogram. Don't sweat the small stuff.

Lower-case T + Right Superscript H
[tʰ], IPA 103 + 404
Release less obviously bursty here, but the gap is unmistakeable. Transcribed as aspirated because of the longer release noise/VOT.

Barred U
[ʉ], IPA 318
Again, getting strict about my IPA. This is not a back vowel. It is however quite round. So even though this has the same formants as the barred-i we've seen (and similar to the small-cap i's we may be used ot seeing, the down-trend in the F2 indicates increasing rounding (or backness) during the articulation of this vowel. Which is typical of post-alveolar /u/ (reflecting its merger with /ju/ in my dialect). But as round as it gets, it don't get anywhere near 'back'. So transcribed as round(ing) and central. And high more than anything else.

Lower-case T
[t], IPA 103
One final plosive, preceded with creakiness (utterance-finally, this could just be low pitch, but more likely it's the combination of low pitch and glottalizing a coda plosive). The release is sharp, and tilted to the high(er) frequencies (possibly brought down a little by lip rounding from the preceding vowel?). Noise like that is atypical of final velars or labials.