The tenor clef is almost identical to the alto clef visually. The only difference is that middle c is moved up a line like this:
___
\
----/------------- E
\
----->------------ Middle C
/
----\------------- A
|
----|------------- F
|
----/------------- D
__/
Most of the time, the tenor clef is used to write music for bassons, chellos, tenor horns, and tenor vocalists.
The symbol for this clef is the same as the alto clef and is also called the c clef because the position of the center of the symbol shows were middle c is located.
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