Many regard the deep sonority of the male choir and the „athmosphere of monasteries" as the only becoming and authentic setting for the Gregorian chant. We do already know that it was exactly the alteration or consonance of high and low tones that characterized most the typical mediaeval performance of the Gregorian chants. Male voices were generally combined with children’s voices, and children sang perhaps more often alone, without being accompanied by male choir than the latter without children’s voices. The numerous women congregations of the Middle Ages were also singing the same kind of music; keeping this in mind women’s performance should not be dismissed as unauthentic, either. Moreover, available data bear evidence of the mediaeval practice of singing Gregorian chants by a combination of male and female voices. Their twentieth century performance can hardly do without the typical sound effect of mixed voices, particularly if certain larger items are performed. We are at a loss to invoke the mediaeval liturgy sung with alternate roles under the present conditions unless we vary within the 15 or 20 minute cycle smaller and larger ensembles, low and high or mixed voices, solo and full choir –not in a fancy disorder but according to a premeditated sequence, paying constantly heed to the regularities of the genre. (J. Szendrei – L. Dobszay – B. Rajeczky: Magyar Gregoriánum, Preface)