Voice type in baroque operas. Except for a few very rare voices (such as the American male soprano Michael Maniaci or singers with a disorder such as Kallmann syndrome), singers called countertenors generally sing in the falsetto register, sometimes using their modal voice for the lowest notes. Historically, there is much evidence that the countertenor, in England at least, also designated a very high tenor voice, the equivalent of the French "haute-contre". Until about 1830, all male voices used some falsetto-type voice production in their upper range. Countertenor voices span a broad range, covering E3 to E5. Countertenor subtypes: Countertenors are often
Terminology model an object-oriented database schema, is can be transformed without loss of information into an object-oriented database schema. Thus, the terminology model is a method for problem analysis on the one side and a mean of defining database schema on the other side. Several terminology models have been developed and published in the field of statistics: Terminology model A terminology model is a refinement of a concept system. Within a terminology model the concepts (object types) of a specific problem or subject area are defined by subject matter experts in terms of concept (object type) definitions and definitions of subordinated concepts