Unaspirated vs. Voiceless

Pablo asked about some sounds I'd like to comment on in his query
"Strange phonology": aspirated trill and aspirated nasals.

An important distinction has to be made about voiceless sounds and
aspirated sounds. Some has claimed that Welsh and some other
languages have aspirated trills. Some have claimed that some
languages have aspirated nasals. But one has to make sure that these
claims are not what is really voiceless trills or nasals. IMO,
aspiration requires two things; a glottis that is spread apart and a
long timing delay of voicing.

To my understanding, the so called aspirated trill in Welsh for
instance is in fact simply a voiceless trill. From what I have heard
of Welsh, there is a spread glottis, but the delay in voicing is not
long enough in my opinion to be called a truly aspirated trill.
Perhaps that's just me, and I'm NOT an expert on Welsh. I would say,
however, that they indeed must exist somewhere.

On the other hand, I know that aspirated nasal stops DO exist. These
are not what you would call voiceless nasal stops which do not have
a long timing delay in voicing. In Burmese for instance, the so
called aspirated nasal stops are in fact just voiceless with no
aspiration. There is a very brief period of voicing just before the
stop is released. On the other hand, there are other SEAsian
languages and Tibeto-Burman languages that really have what I'd call
truly aspirated nasal stops. There is no short period of voicing
before the release of the stop. The spread of the glottis persists
even after the stop is release, and voicing only occurs after the
release - roughly halfway through the following vowel sound.

-kristian- 8-)