Ottava Bassa
The sign that tells the player to sound a passage an octave lower than written
Related
Ottava bassa, written 8vb or 8va bassa, is placed below the staff and tells the player to sound the covered notes an octave lower than written.
Its main job is to remove ledger lines from the low register, so it appears in double bass, piano left hand and organ pedal parts. Where the dotted line ends, the written pitch returns; loco may be added for clarity.
Older scores sometimes put 8va below the staff to mean the same thing, so read the position and the context. Modern practice prefers 8vb, which is unambiguous and cannot be confused with 8va above.
Sources
- 低八度记号的写法与历史用法，参 The New Grove Dictionary of Music and Musicians, "Octave"；本文为原创表述
Used for fact-checking only; all prose is original.