Coll'ottava

What it means

Coll'ottava, Italian for “with the octave,” is a performance instruction: the written notes are additionally played or sung an octave higher or an octave lower, depending on whether the marking appears above or below the staff. The notation itself stays unchanged; the doubling is purely a matter of performance.

In the notation

The instruction appears as the words coll'8 or coll'ottava above or below the affected passage, often with a dashed line showing how long it applies. It ends with a closing bracket or the end of the dashed line.

Musical use

Coll'ottava is used to reinforce a part or give it more fullness and carrying power, for instance in orchestral writing when a melody is meant to sound in several octaves at once, or in piano writing to make a passage sound fuller. Unlike the related signs 8va (play an octave higher) or 8va bassa (play an octave lower), which replace the written pitch, coll'ottava adds the extra octave without replacing the original note.

Coll'ottava should therefore be clearly distinguished from 8va: with 8va only the octave register is shifted, while with coll'ottava a second, octave-displaced part is added to the one originally written.

Performance practice

When you see coll'ottava, check carefully whether the marking sits above or below the staff, since that determines whether the doubling sounds higher or lower. Make sure the doubled octave doesn't sound louder than the main line, so the actual melody keeps the lead.