Yiddish phonology

There is significant phonological variation among the various Yiddish dialects. The description that follows is of a modern Standard Yiddish that was devised during the early 20th century and is frequently encountered in pedagogical contexts.
Consonants.
As in the Slavic languages with which Yiddish was long in contact (Russian, Belarusian, Polish, and Ukrainian), but unlike German, voiceless stops have little to no aspiration; unlike many such languages, voiced stops are not devoiced in final position. Moreover, Yiddish has regressive voicing assimilation, so that, for example, ('says') is pronounced and ('foreword') is pronounced .
Vowels.
The vowel phonemes of Standard Yiddish are:
In addition, the sonorants and can function as syllable nuclei:
 and appear as syllable nuclei as well, but only as allophones of , after bilabial consonants and dorsal consonants, respectively.
The syllabic sonorants are always unstressed.
Comparison with German.
In vocabulary of Germanic origin, the differences between Standard German and Standard Yiddish pronunciation are mainly in the vowels and diphthongs. Examples are the German long as in "Vater" ('father'), which corresponds to in Yiddish , and the German long and long , which correspond to diphthongs in Yiddish ( and ). Yiddish lacks the German front rounded vowels and . They are replaced in Yiddish by (in the case of the short ), (in the case of the long ) and (in the case of ), respectively.
Diphthongs have also undergone divergent developments in German and Yiddish. Where Standard German has merged the Middle High German diphthong "ei" and long vowel "ī" to "ei" (pronounced ), Standard Yiddish has maintained the distinction between them as and , respectively. The German (as in "kaufen", 'buy') corresponds to the Yiddish (in ); lastly, the German , as in "Deutsch" 'German') corresponds to in Yiddish (in ). Another difference is that the vowel length distinctions of German do not exist in Standard Yiddish, although in most cases they were kept disambiguated by other means, such as a change in the vowel quality of (usually) the long vowel.
Yiddish has some coincidental resemblances to Dutch in vowel phonology, which extend even to orthography, such as Dutch "ij" versus Yiddish "tsvey judn", both pronounced /ɛɪ/; and Dutch "ui" (pronounced /œy/) versus Yiddish "vov yud" (/ɔj/). For example, the Yiddish "to be" is זיין, which orthographically matches Dutch "zijn" more than German "sein", or Yiddish הויז, "house", versus Dutch "huis" (plural "huizen"). Along with the pronunciation of Dutch "g" as /ɣ/, Yiddish is said to sound closer to Dutch than to German because of this, even though its structure is closer to High German.
There are consonantal differences between German and Yiddish. Yiddish deaffricates the Middle High German voiceless labiodental affricate to initially (as in "funt", but this pronunciation is also quasi-standard throughout northern and central Germany); /pf/ surfaces as an unshifted medially or finally (as in and ). Additionally, final voiced stops appear in Standard Yiddish but not Northern Standard German.