The Spring Harp is played by manipulation the springs, rods, strings, or any combination; it is an instrument made for experimentation. The rods are standard 1/4”-20 thread, one of the easiest sizes to find. New threaded rod of different lengths can be quickly connected for new pitches and tones. Pairs of nuts can be threaded on near the ends to lower the pitch, or used to attach other objects like sheet metal, small cymbals, glockenspiel bars, etc. The springs can similarly be replaced or cut to different lengths as desired. 

Tuning the strings to match the frequency of the rods will cause them to sympathetically vibrate when the rods are played, which creates a sort of sustaining reverb. Tuning them just slightly off the pitch of the rods can add a beating effect as well. 

Rods can be fine tuned by loosening the nuts, and threading them small amount further in or out before retightening to raise or lower the pitch.