Sentence:  No wonder, for the pulpit had been placed in exactly the most inaudible situation, and the Hall, however well calculated for purposes of feeding, and holding examinations, was a most <WSD>unacoustic</WSD> place to speak in. 
Meaning of the word marked with <WSD> tags:  Having poor acoustic properties; not conducive to the projection of sound; tending to muffle or muddy sounds.