Pronunciation of ん before a fricative


I've seen many questions asked about the ん sound, both on this site and
others, but I'm still uncertain about how it should be produced before a
fricative (e.g. さ, し, ひ, ふ). So I'm hoping someone can give a good, thorough
answer if I ask about it specifically.

Different sources seem to give different pronunciations. Some sources say it
is similar to the English n or ng sound, but with the same place of
articulation as the following sound. So if it is followed by s it would be a
lamino-alveolar nasal. Some sources say it is like a nasalized う. Other
sources simply say it is a nasalized vowel.

So is one of these correct and the others incorrect. Are none of them correct.
Or does it vary by speaker. If it varies, is any pronunciation commonly
regarded as standard and/or more neutral. The opinions of native speakers or
those familiar with Japanese linguistics would be especially appreciated.




Before さ and し it is weakened or incomplete. When ひ or ふ come after ん in a
word (or compound word), they are transformed to the non-fricatives ぴ and ぷ .
E.g.

  * [反比例]{はん・ぴ・れい} 
  * [染筆]{せんぴつ} 
  * [選評]{せんぴょう} 
  * [認否]{にん・ぴ}

which at least doesn't conflict with your implicit assertion that ん followed
by a non-fricative is, or historically was, more pleasurable to utter than ん
followed by a fricative. Of course changing fricatives to non-fricative occurs
frequently in second syllables anyway, e.g. the older pronunciation
[日本]{にっぽん}, so that could be coincidental.

Notably, relatively new compounds like [計算表]{けい・さん・ひょう} and [新福島]{しん・ふく・しま}駅
don't replace the fricative. Also, the modern pronunciation [日本]{に・ほん} doesn't
replace the fricative.

I personally find it is more emotive to say [日本]{にっぽん} than [日本]{に・ほん}, but
choose according to TPO.

