The Emancipation of European Jews induced in them an urge to be integrated into the surrounding culture. The relative sense of freedom encouraged new trends of thinking influenced by the 18th-century ideology of Enlightenment, especially as presented by its most important Jewish proponent, the philosopher Moses Mendelssohn (1729–86). Together, the social and ideological changes effected considerable modifications of the Ashkenazi synagogue practices and caused major changes in the liturgical music of the Jews in central and western Europe. Some of the innovations established in German-speaking countries and in France were emulated later in eastern Europe.
One of the most important manifestations of the new trends was the rise of the Reform Movement in Germany during the early decades of the 19th century. The early Reformers, such as Israel Jacobson (1728–1828) in Seesen (Westphalia) and David Friedländer (1750–1834) in Berlin, changed the traditional siddur (prayerbook) by abolishing texts that seemed to them controversial and by substituting new prayers in German for the old ones in Hebrew. They made considerable alterations in the customs and ceremonies of the service. Above all, they introduced the organ into the synagogue and reduced the role of the traditional hazzan. The main musical innovation was the congregational singing of chorales in Hebrew or German with organ accompaniment, mostly to melodies adopted from the Protestant Church. The traditional chanting of the scriptures according to the te'amim was abolished and the weekly portions from the Pentateuch and the books of the Prophets were merely declaimed. The model for many Reform synagogues was the Hamburg Temple, which was dedicated in 1818. However, the attempt made there to combine the modern innovations of Berlin with some of the oldest melodies of the Sephardi rite – as introduced by the Portuguese hazzan David Meldola (1780–1861) – failed.
The innovations of the Reform temples (as Reform synagogues were often known) aroused bitter controversy among rabbis and scholars. A collection of rabbinical responsa, Noġah ha-sedeq (1818), in favour of the new practices triggered the publication of a vast polemic literature that dealt among other things with musical issues, especially the use of the organ in the synagogue.
19th-century Emancipation also helped change the musical practices of the traditional synagogue. The modern quest for aesthetics and decorum was manifest in the new synagogal regulations (Synagogenorderungen) issued by various communities and encouraged by the state. The bylaws discouraged and sometimes forbade old musical practices, especially those that developed during the 17th and 18th centuries. Of special importance was the disappearance of the meshorerim (see above, §3(iii)) and their gradual replacement by the modern choir. With the decrease in the meshorerim practice, training hazzanim through apprenticeship was replaced by regulated study in teachers’ seminaries, which were supervised by the state. Many cantorial students learnt their chants from notated music rather than from oral tradition. To meet the growing demand for written chants, several manuals of cantorial recitatives appeared in print (e.g. Moritz Deutsch's Vorbeterschule, Breslau, 1871). This and a growing distaste for the old flamboyant embellishments caused a major revision in cantorial recitative style. The recitatives were simplified or ‘purified’ and were frequently written and executed in common time.
Various attempts were made to establish services that would stand in mid-stream between the Reform and Orthodox practices. The most influential of the so-called Moderate Reform synagogues was the Seitenstettengasse Temple in Vienna (dedicated 1826). Under the guidance of Rabbi Isaac Noa Mannheimer (1793–1865) its liturgical practices were for the most part strictly traditional. The innovations were the long weekly sermons in German and the new liturgical music introduced by Salomon Sulzer (1804–90). In addition to the ‘purified chants’ and recitatives that he edited, Sulzer sang new compositions for hazzan and an a cappella four-part choir of boys and men in a Classical style. The choral compositions, which were sung in Hebrew, were composed by Sulzer himself, or commissioned from other composers, Jewish and non-Jewish, such as Joseph Fischhoff (1804–57) and Ignaz von Seyfried (1776–1841). Even Schubert contributed to a Hebrew composition – a setting of Psalm xcii (d 942).
The Vienna Temple soon became the focus for the hazzanim of Central and eastern Europe and its influence was further enhanced after 1838 when Sulzer published the first volume of his Schir Zion, containing selected compositions of the Vienna Temple music (the second appeared in 1865). Synagogues following Sulzer's model sprang up first in the Austro-Hungarian Empire, and later in Germany.
A similar attempt to combine a traditional service with contemporary music was made by Samuel Naumbourg (1815–80) in Paris. With the encouragement of the French government, he proceeded to reshape the music of the Paris synagogue, aiming to create a model for all the French Jewish communities, which were united under the governmental system of Consistoires israélites. Naumbourg's Zemiroth Yisrael (1847–64), which contains compositions for hazzan and male choir, consists of traditional chants and recitatives in the south-German style and modern compositions influenced by French grand opéra choruses. Naumbourg's influence spread far and wide in France and its colonies.
The innovations of Sulzer and Naumbourg served as examples to English hazzanim, who developed similar repertories of synagogal choral music. The London school was created by Simon Asher (1841–79) and his disciple Israel Lazarus Mombach (1813–80), and reached its peak with the works of Marcus Hast (1871–1911). The music of the modern Ashkenazi synagogues of London was sung in similar houses of worship throughout the British Empire.
During the 1870s, the musical centre of the Moderate Reform Movement shifted to Berlin. The great synagogue on Oranjenburgerstrasse (dedicated 1866), which possessed excellent hazzanim, a large boys’ and men's choir and large organ, was the haven for the music of Louis Lewandowski (1821–94), who served as its choirmaster and music director. Lewandowski, perhaps the most gifted composer of Ashkenazi liturgical music in the 19th century, introduced the Romantic, Mendelssohnian style into the synagogue. His two publications, Kol rinnah u't'fillah (1871, a hazzanic manual with compositions for two-part choir) and Todah w'simrah (1876–82, compositions for hazzan and choir with optional organ accompaniment) became the main source of musical repertory for Moderate Reform synagogues. Many of his compositions were also sung in Reform and Orthodox synagogues.
In the major cities of eastern Europe, a modern type of chor-shul (Yiddish: ‘choral-synagogue’) was established, in which fashionable music by Sulzer, Naumbourg and Lewandowski was sung together with the old, flamboyant east European cantorial recitatives. Such east European composers as Nissan Blumenthal (1805–1903), David Nowakowsky (1848–1921) in Odessa and Eliezer Gerovitsch (1844–1913) in Rostov on the Don, strove to find a musical idiom that would combine the German harmony and counterpoint with the east European modality and idiomatic embellishments. Their compositions tended to be long, with many textual repetitions and were usually intended to display the virtuosity of the hazzan.
In the USA, the first Reform congregations, such as the Reform Society of Israelites in Charleston (established 1824) or Temple Har Sinai in Baltimore (1842), adopted the practices of the Hamburg Reform Temple and adapted them to the needs of the American community. American Reform temples usually abolished the office of hazzan; the music was led by the organist and performed by a mixed choir and occasional soloists. Students of Sulzer, such as Jacob Fraenkel (1807–87) and Morriz Goldstein (1840–1906), served the Moderate Reform synagogues and exerted a lasting influence on American synagogue music of all denominations. Fraenkel and Goldstein's collection of liturgical music, Zimrat yah (1871–86) was disseminated and used widely. Typical of the American style of post-Emancipation music are the works of Sigmund Schlessinger, who was born in Uhlen (Württemberg) in 1835, and emigrated to Mobile, Alabama, in 1860, where he died in 1906. His compositions, which were most popular in American Reform congregations at the beginning of the 20th century, are settings of the American Reform Hebrew Union Prayerbook in the Germanic Romantic style, with some adaptation from Italian opera.