Sin' al fine
“Until the end”.
What it means
Sin' al fine is a shortening of sino al fine and means “until the end.” The phrase belongs among the instructions that control repeats and has the same meaning as al fine.
It stands in connection with da capo or dal segno and fixes how far to play after the jump back: up to the point marked fine, at which the piece ends. Da capo sin' al fine thus means “from the beginning to the end.”
Between sin' al fine and al fine there is no musical difference; they are two linguistic variants of the same instruction. Which one an edition uses depends on the habit of the composer or publisher.
The phrase can also be used more generally, to let an instruction apply until the end of a piece, for instance sempre piano sin' al fine.
In the notation
The phrase stands at the end of the section after which the jump back occurs, together with D.C. or D.S. The word fine stands over the point at which the piece ends, often over a double bar in the middle of the notated text.
Musical use
Like al fine, the phrase serves to notate forms with a recurring opening section space-efficiently. It appears in three-part forms, in minuets with a trio, in arias, and in many dances and songs.
Sin' al fine means “until the end” and usually stands in connection with another marking, for instance sempre legato sin' al fine. It calls for maintaining an instruction until the close of the piece or section. In repeat instructions it appears as da capo sin' al fine, back to the beginning and to the end.
Performance practice
Before the first run-through, look for the fine point and mark it distinctly. Clarify whether repeat signs apply on the second pass. Take care that the close at the fine point sounds like a close. And check, with general use, up to where the instruction applies.