YODH
י
VOICED PALATAL UNROUNDED SEMI-VOWEL [j]
Tiberian Hebrew yodh is pronounced like English "y".
[j]
י
Hidayat al-Qari
So, the total number of places of articulation are six, five primary and one secondary. The middle of the tongue is the place of articulation of five letters, namely גיכרק.
Translation from Khan (TPTBH II.L.1.3.6)
פגמלה אלמחאל סתה כמסה אצול וואח[ד] פרע פוסט אללסאן מחל לכמסה חרוף והי ג̇י̇כ̇ר̇ק̇
Text from Khan (TPTBH II.L.1.3.6)
Hidayat al-Qari
Know that when you pronounce (the word) שִׁין, you pronounce three letters from three different places of articulation, the shin from the teeth, the yod from the middle of the tongue, in its wide part, and the nun from the extremity of the tongue and the flesh of the teeth.
Translation from Khan (TPTBH II.L.1.3.8)
ואעלם אנך אדא לפט̇ת בשין פקד לפט̇ת בג̇ חרוף מן תלת מחאל מתגאירה פאלשין מן אלאסנאן ואליוד מן [וסט] אללסאן בערצ̇ה ואלנון מן טרף אללסאן ולחם אלאסנאן
Text from Khan (TPTBH II.L.1.3.2)
EXAMPLE WORDS:
יְסוֹד
[jaˈsoːoð]
אֵלַי
[ʔeːˈlaːaj]
אֲרָיוֹת
[ʔaʀ̟ɔːˈjoːoθ]
יוֹם
[ˈjoːom]
GEMINATED VOICED PALATAL STOP [ɟɟ]
Yodh with dagesh (i.e., doubled/geminated yodh) is not just held for a longer duration than yodh without dagesh, but it is also pronounced stronger. When you pronounce regular yodh, you let the air continue to flow just like when pronouncing English "y". However, when you pronounced yodh with dagesh, you need to stop the airflow almost as if you were pronouncing "g". This is actually a very important pronunciation difference to observe, since it occurs so frequently in the 3M vayyiqtol verbal forms.
[ɟɟ]
יּ
Commentary on Sefer Yesira
As for jīm, it is in between gimel and yod. This is why the Tiberians pronounce it [i.e. jīm] when (reading) yod with dagesh.
Translation from Khan (TPTBH I.1.10)
ואמא אלג׳ים פפי מא בין אלגימל ואליוד ולד׳לך ג׳עלהא אלטבראניון פי אליוד אלדגש
Text from Lambert (1891, 42–43)
EXAMPLE WORDS:
חַיִּ֔ים
[ħaɟˈɟiːim]
אַיָּלָ֣ה
[ʔaɟɟɔːˈlɔː]
וַיַּשְׁמֵ֣ד
[vaɟɟaʃˈmeːeð]
וַיִּכְתֹּ֣ב
[vaɟɟiχˈtʰoːov]
SOURCES AND FURTHER READING
Khan, Geoffrey. 2020. The Tiberian Pronunciation Tradition of Biblical Hebrew. Cambridge: Cambridge and Open Book Publishers. §I.1.10.