Concerning the "Sticky" post that rowuk made concerning the naming of high notes:
What he posted is not correct. The naming of octaves does not start with Low C. It starts with Low F#. Double G therefore would not be the G above Double C, it's the G below Double C.
Otherwise if you follow his logic, the B below Low C would have to be called "Pedal B".
Starting with Low F#:
Low F# (below Low C)
Middle F# (in the staff)
High F# (on top the staff)
Double F# (above High C)
Using G as an example:
Low G (below the staff)
Middle G (in the staff)
High G (on top the staff)
Double High G (above High C)
Triple High G (above Double High C)
Using F as an example:
Pedal F (below Low C)
Low F (in the staff)
Middle F (on the top line of the staff)
High F (above High C)
I realize many players will call the G above High C a "High G" and they'll call the F above High C, "Top F" and various things like that.
But unless you adopt the system I just outlined, by definition, your pedal register will have to start at the B below Low C, or you'll have to come up with new names for some notes, since if you try to call a G above High C a "High G", that would make the G above middle C a "Middle G" and then therefore you'd have to call the G above Low C a "Low G" - and that would leave you with G below Low C being called "Pedal G". And that wouldn't work very well, would it?