Bach's instrument (5)
I believe the answer is:
organ
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">bach's instrument</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for organ that I've seen before include "Brain, for example - instrument" , "Eg, heart, liver" , "Body part - wind instrument" , "Wind and keyboard instrument" , "May be in the loft" .)