Boss SP-505 Owner's Manual page 28

Quick Start
* When you play pitches using a sample, unwanted space may
occur at the beginning or end of the sound. After the Pitch
function is executed, settings will be made automatically, so
only the necessary portion is sounded. If you want to make fine
adjustments, refer to "Specifying the start/end points of the
sound (Omitting unwanted portions)" (p.46).
Never turn off the power while the display indicates
"Keep Power On!"
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