The choral tunes sung by the congregation were at first not harmonized. Then, as they began to be set in the strict contrapuntal style of the day, it became the custom for the people to sing the melody while the choir sustained the other parts. The melody was at first in the tenor, according to time-honored usage in artistic music, but as composers found that they must consider the vocal limitations of a mass of untrained singers a simpler form of harmony was introduced, and the custom arose of putting the melody in the upper voice, and the harmony below. This method prepared the development of a harmony that was more in the nature of modern chord progressions, and when the choir and congregation severed their incompatible union, the complex counterpoint in which the age delighted was allowed free range in the motet, while the harmonized choral became more simple and compact. The partnership of choir and congregation was dissolved about 1600, and the organ took the place of the trained singers in accompanying the unison song of the people.
One who studies the German chorals as they appear in the hymn-books of the present day (many of which hold honored places in English and American hymnals) must not suppose that he is acquainted with the religious tunes of the Reformation in their pristine form. As they are now sung in the German churches they have been greatly modified in harmony and rhythm, and even in many instances in melody also. The only scale and harmonic system then in vogue was the Gregorian. In respect to rhythm also, the alterations have been equally striking. The present choral is usually written in notes of equal length, one note to a syllable. The metre is in most cases double, rarely triple. This manner of writing gives the choral a singularly grave, solid and stately character, encouraging likewise a performance that is often dull and monotonous. There was far more variety and life in the primitive choral, the movement was more flexible, and the frequent groups of notes to a single syllable imparted a buoyancy and warmth that are unknown to the rigid modern form. The transformation of the choral into its present shape was completed in the eighteenth century, a result, some say, of the relaxation of spiritual energy in the period of rationalism. A party has been formed among German churchmen and musicians which labors for the restoration of the primitive rhythmic choral. Certain congregations have adopted the reform, but there is as yet no sign that it will ultimately prevail.