Type of Voice
Soprano and alto (SA), this arrangement is usually sung by the choir (choir) women or children. Low noise are not always seen as a bass voice choir therefore, should be accompanied by an instrument to strengthen the low tones.
TTBB (Tenor, Tenor, Bass, and Bass) is a the choir sung by a male voice, but the more we come across are male the choir to 3 votes, namely (Tenor, Tenor, Bass) TTB.
Make arrangements for mixed the choir (SATB) is basically create a new song. Soprano voice is usually already there and a melodic essence, although sometimes there is also the principal melody laid on another type of sound, it is the exception.