This type of chant is a form of traditional Orthodox liturgy characterized by a complex polyphony. "Znamenny" literally means "Sign" and is the graphic symbol placed in lieu of the usual musical notes, defining the changes in melody.

Due to its ancient origins dating back to the dawn of the Orthodox Church (around the year 1000), this chant was preserved and perpetuated by the Russian Old Believers, who were resistant to all forms of innovation.

Here is a typical Znamenny chant of the "Russian Old Believers" for Pentecost.

Херувимская песнь демественный роспев / Cherubic hymn znamenny chant - Old Believers