Byzantine music utilizes, similarly to other types of ecclesiastical music systems, a limited number of musical formulae, for each tone, where the formulae are repeated in pieces by using different combinations. We do not discuss, in the next lines, the history or the factors behind this composition style but we look at one of the most important features of this style from a parochial point of view.

Actually, each formla bears in itself quite beauty, majesty and complexity so that it takes years of hard musical studies and experience Byzantine style of psalmody to learn all the fomulae. However, it is amazing to notice that when a psalter lears how to read these formulae, it becomes possible for him/her to read most of the Byzantine compositions at first sight, given the limited number of formulae.

Consequently, it is possible for Byzantine choir with an acceptable level in reading Byzantine music to perform a Byzantine piece "A première vue" in a decent way.

This feature, specific to Byzantine music in addition to performing the Byzantine Isson systetm (second bass voice) joins two opposites: majesty and difficulty of tone on one hand and fluency of reading on another.

Thanks to this specificiality, the Byzantine liturgy could comprise a huge number of texts and pieces (which cannot be entirely rehearsed!) performed by choirs during liturgical services that can sometimes take all night long as in the all-night-vigil service.

During a spiritual retreat of SEM choir to the Holy Mount of Athos - Greece, the will of God gathered SEM with the choir of Vatopedi great monastery in the all-night-vigil service of the feast of Elevation of the Holy Cross. Thus, this recording was brought up, providing excerpts from the service.