Unit of blank" >target="_blank" >glossary/loudness/" class="glossaryLink" data-cmtooltip="48f86ba412fab13f99c823c1d279920d" blank" >target="_blank" >loudness of sound. It is derived from the vocabulary of communication blank" >target="_blank" >glossary/engineering/" class="glossaryLink" data-cmtooltip="51d4e292df2547b72f529a164eb6302a" blank" >target="_blank" >engineering and is the equivalent of the loss in power in 1 mile of blank" >target="_blank" >standard cable at 860 cycles. (Saylor, 1952)