13.6.2 Progressive Devoicing of Fricatives

Voiced fricatives are devoiced after voiceless obstruents, i.e. /v,z,ʒ,(ɣ)/ become /f,s,ʃ,x/. Note that, with the possible exception of a loanword like exact /ɛgˈzɑkt/, syllable-final obstruents will always be voiceless in Dutch.

/v/ becomes /f/                        houtvuur, advies

/z/ becomes /s/                       opzij, afzien

/ʒ/ becomes /ʃ/                        ’t journaal, dit genre

The rule also applies to /ɣ/, if present initially in Southern Dutch, as in aardgas, prinselijk gewaad. Speakers from the West of the country will frequently avoid progressive devoicing of /z/ and /ʒ/, and retain a voiced sound. Since /s/ for /z/ in non-assimilating contexts, as in gezakt (i.e. /xəˈsɑkt/), is heavily stigmatized, the failure to devoice /z/ in an assimilating context like niet ziek, op zee, may be looked upon as a case of overgeneralization, whereby what is essentially a spelling-based rule is applied across the board to any /s/ which is spelled z, regardless of the phonetic context. A similar explanation can be adduced for pronunciations like /ət ʒurˈnaˑl/ for het journaal (standard /ət ʃurˈnaˑl/).

Advice for Dutch learners
You may find that your efforts to pronounce a voiced rather than a voiceless fricative in phrases like this village, if they, eight votes result in pronunciations like */ðɪz ˈvɪləd͡ʒ, ˈɪv ðeɪ, ˈeɪd ˈvoʊts/, where the preceding obstruent is voiced as well. Try to avoid this kind of overcompensation by making sure that a syllable-final fricative remains voiceless and a syllable-final stop is glottalized.

Note, on the other hand, that in words like advice, obvious, exam both obstruents are fully voiced in English.