The name Subtilregal is listed only by Audsley, who says: The name given to an old lingual stop, of 8 ft. pitch, the tone of which was of a soft and agreeable quality, probably differing slightly from that of the Gedämpftregal. Both the stop and the name are obsolete. This name comes from the German word subtil, meaning �subtle�. The names Subtiles Regal and Suptilregal (which may be a misspelling) are mentioned only by Adlung, with no definition; we assume them to be synonyms.