the term "spasm band" refers to a band that uses homemade instruments. indeed, most of the nsb's instruments are modifications of other instruments, or wholly invented by the members. in addition to the homemade instruments, members are encouraged to improvise. the range of the improvisation is such that instruments are not tuned to each other, tempos and time signatures are not imposed, and the members push the ranges of their instrumentation by engaging in constant innovation and ever-increasing volume over the course of a performance.