I have been trying to figure out something about the alveolar flap or tap. I'm not sure whether the Spanish r as in words like "pero", "cero", "caro" and the like is the same as the English sound in words and phrases like "matter", "natalie", "order", "water", "how to" "about a" and the like. At first I thought the sounds were the same. But then I started to do some research and began doubting whether or not they were the same sounds. I began leaning towards them not being the same. But right now I'm in doubt again. I think they might be the same, but I'm still not sure. […] Could you please tell me if there is any articulatory difference between the two sounds or not?
In saying "English", Alexis is of course referring only to AmE. The usual BrE consonant in the middle of water ˈwɔːtə is very different from the Spanish single /r/ in pero ˈpeɾo. This BrE t is voiceless, slow, perhaps somewhat aspirated and indeed often affricated, whereas Spanish ɾ is voiced, and rapid. But in AmE, on the other hand. the etymological t in the words quoted is a voiced tap (‘flap’, say some) that is indeed very similar to the Spanish /r/, and is indeed sometimes transcribed identically, as ɾ.
Are the two sounds merely similar, or are they ‘the same’? Partly the problem is one of asking what we mean when we say that two sounds are ‘the same’. Do we just mean that language learners can safely treat them as equivalent? Or is it deeper than that?
Not all Spanish ɾ are identical. For example, some speakers articulate it with the tongue tip against the teeth, making it dental; but for others it may rather be alveolar. The duration of the closure is usually about 20 ms, but may on occasion be somewhat longer or shorter. The AmE sound is at least as variable, and probably more so. For example, it may not always be fully voiced (particularly for those relatively few Americans who consistently distinguish pairs such as shutter and shudder). Following the NURSE vowel, as in dirty, it may involve a ballistic movement, a true flap, in which the active articulator strikes the passive articulator and continues in the same trajectory, as opposed to the more usual type in which the active articulator ‘bounces off’ the passive, involving an up-then-down movement. In Natalie, battle etc, the tap is unlike anything in Spanish, since it has lateral release. (But some speakers use a glottal stop here rather than a tap. A glottal stop is equally un-Spanish.)
More importantly, perhaps, the tongue configuration before and after the consonant may differ considerably in the two languages, giving rise to different formant transitions in the on-glide and off-glide of the segment we are discussing.
The clincher comes, though, from x-ray tracings. I reproduce this from Ladefoged and Maddieson’s The Sounds of the World’s Languages (Blackwell 1996).
The authors comment
The English speaker has a preparatory raising and retraction of the tongue tip during the preceding vowel […] The tongue is then moved forward to make the contact which is captured in the frame illustrated here, after which it returns to the floor of the mouth. The Spanish tap does not involve any substantial anticipation, but instead has a quick upward and downward movement confined to the tongue tip.
It is possible that in the case of water, the word illustrated here, the preparatory retraction of the tongue tip may be in anticipation of the r-coloured ɚ which follows. Would we find the same retraction in a word such as atom ˈæɾəm? I do not know.
So what is my answer to Alexis? I think we can say that the two sounds are not really exactly identical, but that for language learning purposes we can treat them as if they were.