Utterance initial [ɾ]


According to [The sounds of Japanese (Vance
2008)](http://www.cambridge.org/gb/knowledge/isbn/item1157656/?site_locale=en_GB):

> When /ɾ/ is the first phoneme in an utterance, the tip of the tongue is
> already resting lightly on the alveolar ridge, and /ɾ/ is produced by
> rapidly releasing this contact. Strictly speaking this utterance-initial
> allophone isn't a tap.

  1. Can anyone elaborate on this utterance initial [ɾ] and its allophonic derivation, perhaps giving a reference for further reading? If it isn't a tap, then what is it? It sounds like it might be a voiced plosive, but it doesn't feel similar to either alveolar plosives [t, d]. It certainly sounds like there is an r-quality to it, but I wouldn't know how a plosive might acquire an r-quality.

  2. Are you actually realizing, and furthermore aware of, an allophonic variant of [ɾ] (specifically the apparent utterance-initial allophone)?




[Wikipedia](http://en.wikipedia.org/wiki/Alveolar_lateral_flap) seems to say
it is alveolar lateral flap, as opposed to the otherwise alveolar (central)
flap. If you are serious, maybe you might want to try [the
article](http://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=1799940)
cited there. Trying this with myself, I seem to get the difference. I seem to
be able to freely alternate an initial alveolar lateral flap with a centered
one, but not a non-initial alveolar flap with a lateral one.




[Wikipedia](http://en.wikipedia.org/wiki/Alveolar_lateral_flap) seems to say
it is alveolar lateral flap, as opposed to the otherwise alveolar (central)
flap. If you are serious, maybe you might want to try [the
article](http://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=1799940)
cited there. Trying this with myself, I seem to get the difference. I seem to
be able to freely alternate an initial alveolar lateral flap with a centered
one, but not a non-initial alveolar flap with a lateral one.

