A Cappella sheet music

Read the voicing before anything else

SATB is standard four-part mixed. SSAA and TTBB are upper and lower voices respectively. SAB is a three-part compromise for choirs short of men, and SSA for upper-voice groups.

A divisi marking means a part splits — an "SATB div." piece may need eight independent lines at its climax, which a small choir cannot cover however well it sings. The listing usually states this; the cover sometimes does not.

Octavos are sold per singer

Choral music is published as octavos: a single unbound piece, priced per copy, bought one per singer. Photocopying instead is both illegal and the reason many small publishers no longer exist. For a choir of thirty, budget thirty copies.

Some publishers now sell a licence to print a stated number of copies, which is cheaper for large groups and legitimate. Look for wording about copies included.

What is free

The Renaissance and early Baroque a cappella repertoire — Palestrina, Byrd, Tallis, Victoria, Lassus — is out of copyright and available complete from the choral public-domain archives, usually with modern clefs and note values already applied. It is the single best-served corner of free sheet music anywhere.

Modern arrangements of popular songs are not free, and an unlicensed arrangement of a copyrighted song cannot legally be performed even if you found the sheet at no cost.