The loud? block is a boolean block in the Sensing category that reports true if loudness is greater than 10[1] and false otherwise. It originates from Scratch, but the value that is detected was changed from 30 to 10 in Scratch 2.0 and was made hidden in a 2.0 beta build.

loud?
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Caption
Block Type Boolean Block
Category / Extension Sensing
Status Who tf uses status

Workaround

This block can be worked around by detecting if the value of the loudness reporter is greater than 10 by using the () > () block:

(loudness) > [10]

References