Posted by Scott on February 24, 2003 at 16:10:38:
In Reply to: register-french horn posted by Patrick on February 24, 2003 at 15:54:10:
Horns transpose up a fifth. So, middle C is written second line G on the treble clef staff.
For range, you won't want to go above a written F for high schoolers. College and above you can go up to written high C (two ledger lines above the staff) but that is very difficult. For practical playing, you won't want to go much below the staff (around written G), but you'd be amazed how low an accomplished hornist can play.
For future reference, you may want to pick up an orchestration or instrumentation book like the Kennan, or if you're serious about it, the Blatter. Both are standard in college orchestration classes.
Hope this helps.
-Scott