The Hebrew letter Ṭet (ט), which corresponds to the ninth letter of the alphabet, has undergone significant phonetic evolution since ancient times. In Proto-Semitic, it was likely pronounced as an emphatic or pharyngealized voiceless dental stop [tˤ], distinct from the simple voiceless dental stop Tav (ת).

1. Proto-Semitic Pronunciation (circa 3000–2000 BCE)

• Ṭet (Ṭēṯ) is reconstructed as [tˤ], a pharyngealized or emphatic [t].

• The emphasis (pharyngealization) was produced by constricting the pharynx while articulating the dental [t]. This sound likely had a "dark" or "heavy" quality, distinct from a plain [t].

2. Biblical Hebrew Pronunciation (circa 1000–500 BCE)

• In Biblical Hebrew, Ṭet likely retained its pharyngealized or emphatic nature.

• It was pronounced as [tˤ], a sound similar to the emphatic ط (Ṭāʼ) in Modern Arabic, still preserved in some regional dialects.

3. Shift in Post-Biblical Hebrew (circa 500 BCE–500 CE)

• With the decline of emphatic articulation in post-Biblical and Mishnaic Hebrew, the distinct pharyngealization of Ṭet began to fade.

• It likely merged in some dialects with a plain [t] or a slightly velarized [t̠] but remained distinct from Tav (ת).

4. Medieval and Modern Hebrew

• By the time of Medieval Hebrew, particularly among Ashkenazi and Sephardi communities, the emphatic feature was completely lost, and Ṭet was pronounced as a plain [t], identical to Tav (ת).

• In Modern Israeli Hebrew, Ṭet (ט) is universally pronounced as a simple [t], indistinguishable from Tav.

Summary

In ancient times, Ṭet (ט) was pronounced as a pharyngealized [tˤ], reflecting its emphatic origin. Over centuries, this sound simplified to the plain [t] heard in modern Hebrew.