➀ Set up the equipment as shown in Figure 2. The microphone can be mounted in the microphone hole
below the speaker, or, as shown in the lower insert,
it can be taped to the end of the microphone probe
rod and inserted through the mounting hole so that
nodes and antinodes can be located within the tube.
You can also vary the effective tube length by inserting the movable piston as shown in the upper
insert. The end of the piston rod that is outside the
tube should be supported to avoid putting excessive
strain on the piston.