Boss GT-1000CORE Parameter Manual page 31

Parameter Value Explanation
If this is ON, effects that affect the pitch are
BS MODE
OFF, ON
optimized for bass.
Selects the guitar (input level) that is connected
to the INPUT jack.
This lets you specify for each patch the guitar that
INPUT
SYSTEM,1–10
will be connected.
If you select SYSTEM, the settings of "INPUT" (p.
44) are used.
Effect
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