unsonorous
/ˌʌnsəˈnɔrəs/ or /ˌʌnˈsɒnərəs/Definitions
1. adjective
having a dull, unpleasant, or harsh sound; lacking harmony or musical quality
“The unsonorous creaking of the old wooden floorboards echoed through the empty hallway.”
2. noun
a quality or characteristic of being unsonorous or lacking musical quality
“The unsonorousness of the construction site was a constant source of disturbance for the nearby residents.”