Small octave
Octave range from c to b.
What it means
The small octave spans the pitch range from c to b and is written in the German naming system with small, unmarked letters. It lies one octave above the great octave and one octave below the one-line octave, which contains standard concert pitch a'.
Musical use
For many instruments and lower male voices, the small octave lies in a well-reachable, middle to lower range. In scientific pitch notation it corresponds to C3 to B3. It is thus an important reference range when learning notation, since it lies directly below the one-line octave, often used as a starting point.
The small octave should be distinguished from the great octave, whose notes are marked with capital letters, and from the one-line octave with its raised 1. Naming by small letters without a further mark is a German tradition of pitch notation.
Performance practice
When reading notes in the small octave, first place them in relation to the one-line octave, which is probably more familiar to you, and count one octave down from there. Practise naming the notes in this range aloud, until you can reliably match staff position and note name.