Synagogue voices

The center of synagogue services is the Torah reading, which consists of the most ancient, authentic melodic patterns ("leynen": melodic recitation, “cantillation”). 
The melodies may be improvised or fixed. Most of the melodies of the prayers are improvised, each having its own nusach, or “mode.” The prayers are recited in their own respective nusach. 

In practice, fixed melodies may be performed in several variations, but they resemble one another more closely than the improvised ones. 

The musical liturgy in the synagogue follows the text of the prayers.

The 19th-century renewal of worship services sought to elevate liturgical music to the level of classical music while preserving traditions. In addition to creating harmonic unity, it revived the musical form that, according to the testimony of Scripture, characterized worship services in antiquity. (Hazan, choir, antiphonal form). In addition to traditional melodies, many of the works by cantor-composers became folk songs, which both Orthodox and Neolog worship services in Ashkenazi regions have adopted as their own.