## Mid-measure key signatures
Mid-measure key signature is essentially a key signature before a sound unit:
When you create a mid-measure key signature, it affects all the following page lines:
Sound units in different voice and staves adjust their horizontal position if a mid-measure key signature is added, so that synchronization of sound units is not getting ruined:
Also you can see that, key signature applies for all staves. And if you don't specify a mid-measure clef when you declare a mid-measure key signature, then mid-measure clef will be the same as the one you declared for a stave. If you didn't declare a clef for a stave, then treble clef will be considered as a mid-measure clef.
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