Pipe natural frequencies are dependent on the geometry of the pipe where the pipe length is the main contributor in regulating the natural frequencies. The boundary conditions are another major contributor because the acoustic waves in the pipe will produce standing waves because of the reflections at the boundary conditions. Making one of the boundary conditions location in the pipe adjustable will allow for the length of the pipe to be modified and therefore change the natural frequencies of the pipe. This adjustable pipe provides a means for introducing undergraduate students to an inexpensive setup to test pipe length in changing the natural frequencies of pipes and the associated sound pressure level within the pipe. Helmholtz resonators are passive devices that can absorb acoustic energy from an acoustic enclosure. These resonators have three major variables that are used to determine the resonant frequency of the resonator and therefore the frequency at which the resonator will absorb acoustic energy. Designing a resonator where one of the variables can be altered allows the resonator to be tuned to a specific frequency. The adaptive Helmholtz resonator provides undergraduate students an inexpensive setup to tune a resonator and test how acoustic pressure is dampened by the energy absorption of the resonator.