Vocal Ensemble OKTOIH (Beograd, 2000.), was established at the initiative of conductor Aleksandar Sasa Spasic www.sashaspasic.com and several of his associates - a singer, with a basic idea to form a chamber ensemble with particular attention to research and execution chamber vocal and vocal-instrumental works. Oktoih is conceived as a male octet and double mixed with a semi-octet mode of action and a mobile system. The total number of singers varies depending on the type and difficulty of the program, so it may be in the formation of 24 or a maximum of 32 singers, which is a standard number for a chamber choir. Oktoih is extremely convenient evaluated on concerts and performances, which are: National Library of Serbia, Easter concert at the chamber opera\\\'\\\'Madlenianum\\\'\\\'concert...