The 't' and 'd' (dental & postalevolar plosives) sound so close together.
Hold your hand in front of your mouth and feel the difference in pressure when you pronounce the first sound of the word "tune" versus the word "dune". This will let you feel that puff of "aspiration." Next, try putting your fingers over the front of your throat, (on your layrnx or where the Adam's apple is on men), and pronounce the sounds slowly. You may be able to feel the difference when your vocal cords start to vibrate as you say the "d" sound. In native English speakers this happens shortly after the pressure is released from your tongue, while in the English "t" sound, the vibration doesn't start until the vowel does. The "d" sound in the example from the chart has the vocal cord vibrations start immediately as the pressure is being released.
The aspiration will be even more obvious if you try speaking into a microphone.
Native speakers have the advantage in spoken conversation. They quickly understand not just the word, but the context. No native speaker would ever confuse "Give that document to Ted" with "Give that document to dead" since the latter is nonsensical. Even if you actually said "dead", most people would interpret it as "Ted" without even noticing anything odd about your pronunciation. (In fact, in a context like that between two vowels, it's entirely possible that you would keep your vocal cords buzzing and produce a "d" even if you'd meant to say "t").
There's very little blame to be placed on liaison, since word boundaries are unclear in every language, including languages that e.g. don't allow syllable-final consonants. English speakers feel like they have a strong grasp of where word boundaries occur because of the orthographic space, but the space in the writing system does not coincide with word boundaries in the language; it is heavily conventionalized.
That is not what "phoneme" means. They are different sounds, but they aren't different phonemes in either language; to be different phonemes, the same language would have to consider them different. Neither does -- in both cases, one is "/t/" and the other is "weird /t/".
However, since there is no alveolar [t] in Spanish, it will generally just be transcribed as /t/ rather than having to put the diacritic on all the time.
What I was talking about was how the Spanish /t/ has the tip of the tongue just a bit further forward, so that it touches the back of your teeth. English /t/ is, for most people, purely alveolar, so there's no teeth contact.
It’s even more crucial with d. An English native speaker who is a beginner in Spanish will pronounce tened in a way that will be interpreted by Spanish speakers as tener.
Obviously this is a spectrum; some transcriptions are so broad that they transcribe the english <r> as /r/ when the context is clear that we're talking about english, even though it should properly by /ɹ/. And in my narrow transcription, I didn't bother to notate vowel length, because it didn't matter for the given example.
(Note: I use <> for orthography (how it's written in the language), // for broad transcription, and, and [] for narrow transcription)
Ah yeah, that's true. This is because most Spanish speakers pronounce /t/ as denti-alveolar (the tip of the tongue touches the back of the teeth) while most English speakers pronounce /t/ as purely alveolar (the tip of the tongue stops at the back of the alveolar ridge). I'm not sure why the IPA chart doesn't differentiate these specific phones, honestly. I imagine it's because although the sounds are very different cross-linguistically, maybe there aren't any languages where these phones are contrastive and thus they don't warrant separate glyphs in the IPA. Still, I'd love to see them!
That said, I think this is actually a relatively uncommon case in the IPA, because in addition to this simple chart the IPA also specifies a number of diacritics for more complex and precise transcriptions. These diacritics are often not used in broad transcriptions within a single language because most languages don't differentiate phones at this level in a contrastive manner. But in a narrow transcription, the diacritics are used as appropriate, generally to help the transcriber make a point about what is noteworthy in that transcription.
For instance, in English let's consider the "t" as you mention. We'll look at "tap" and "pat". The broad transcriptions for these words are /tæp/ and /pæt/, respectively. But the narrow transcriptions would be more like [tʰæp̚] and [pʰæt̚] (Note that broad transcriptions are phonemic and given between slashes, while narrow transcriptions are phonetic and given between brackets). What this shows is that, in English, syllable-initial voiceless stops are aspirated (indicated by the little "h"), while word-final voiceless stops have no audible release (indicated by the angle symbol, known as "corner"). So in addition to the main letter glyphs of IPA, there are tons of diacritics that help you write your transcriptions more precisely!
It's because sounds vary continuously, but the IPA is by necessity discrete. (A problem that is much worse for vowels, but still comes up for consonants.) You have to collapse variation somewhere.
The IPA notably doesn't have dedicated symbols for affricates. (Sounds that consist of a stop immediately followed by a fricative in the same location, like "z" in "pizza" or "ch" in "chill".) So English "ch" is represented /tʃ/, or if you want to be really explicit there's an affrication diacritic.
Recognizing that affricates consist physically of a colocated stop and fricative was felt to be a theoretical advance. But there's a funny story -- Peter Ladefoged went to document a language somewhere (the Americas?) and was proud to use the IPA to record its sounds. He insisted on it.
He insisted on it even after discovering that the language in question made a phonemic distinction between affricated tʃ, which he represented by /tʃ/, and /t/ followed by /ʃ/ without affrication, which he was forced to represent by /t.ʃ/. This would have been much easier to understand with a more bespoke system representing the two adjacent sounds as /tʃ/ and the affricate as /č/.
I get the continuous vs discrete aspect for sure, but you'd think we'd at least have different symbols for each place of articulation! /t/ crosses four different places (dental, denti-alveolar, alveolar, post-alveolar) and the best we can do is cut that down into two groups of two places with the dental diacritic which says "some teeth contact". I think if I were to design such a transcription system from scratch, I would try to make it at least possible to express each place/manner combination, but that's just me!
Looking at the example sidethread of Mandarin pinyin "q", it is a laminal palatal aspirated affricate. Its equivalent in English is a much more complex issue than the equivalent of a Spanish "t", which everyone agrees on. The "q" may be perceived as a "ts" (witness "Tsingtao beer"), which is the English sound combination most closely matching the positioning of the tongue, though not the positioning of the restriction in airflow, or it may be perceived as "ch", which is the English single sound most closely matching the place and manner of articulation. Different English speakers may even disagree on the interpretation while listening to the same speech, and the same English speaker will disagree on (or be confused about) the interpretation when listening to the same speaker produce the sound multiple times.
There are languages that distinguish retroflex stops from alveolar stops, and IPA obliges those languages with different symbols for the two places of articulation. Do you know of a language that distinguishes alveolar stops from dental stops?
> There are languages that distinguish retroflex stops from alveolar stops, and IPA obliges those languages with different symbols for the two places of articulation. Do you know of a language that distinguishes alveolar stops from dental stops?
I actually mentioned this in the top comment:
> I'm not sure why the IPA chart doesn't differentiate these specific phones, honestly. I imagine it's because although the sounds are very different cross-linguistically, maybe there aren't any languages where these phones are contrastive and thus they don't warrant separate glyphs in the IPA.
What I meant in my most recent comment was that, if I were going to create a new IPA from scratch, I would probably try to have some diacritic or distinct symbol for each place of articulation, such that any possible place/manner combination could be expressed uniquely. As it stands, the presence of distinct symbols in the IPA seems governed by whether there are examples of real-world languages in which phones are considered contrastive. This is perfectly pragmatic, but it leaves me feeling disappointed that I can't easily express something that is right there on the chart! Having <t> correspond to 3-4 places of articulation with only a diacritic to distinguish 1-2 of those is disappointing, even if it's technically sufficient for any transcription within a given language.
I think this is a pretty spot-on observation. IPA does offer a bunch of diacritics for making more narrow transcriptions. For instance, Spanish's dental <t> is [t̪].
However, the narrower the transcription, the less applicable it is to a language in general. Things like dialectal and even individual differences start to come into play. So in general transcription will only be as narrow as necessary to achieve some point.