Closed Organ Pipes
An acoustic pipe closed at one end and open at the other, having a displacement node at the closed end and an antinode at the open end.
Governing formula
f_n = n v / (4 L) (n = 1, 3, 5, ...)
SI unit
Hz
In depth
Closed pipes produce strictly odd harmonics (1st, 3rd, 5th...). For the same length, a closed pipe's fundamental pitch is an octave lower than an open pipe.
Examples in the real world
Clarinets and pan flutes acting as closed acoustic pipes.