Broadband viscoelastic spectroscopy (BVS) is a technique for studying viscoelastic solids in both bending and torsion. It provides the ability to measure viscoelastic behavior over eleven decades (orders of magnitude) of time and frequency: from 10 to 10 Hz. BVS is typically either used to investigate viscoelastic properties isothermally over a large frequency range or as a function of temperature at a single frequency. It is capable of measuring mechanical properties directly over these frequency and temperature ranges; as such, it does not require time-temperature superposition or the assumption that material properties obey an Arrhenius-type temperature dependence. As a result, it can be used for heterogeneous and anisotropic specimens for which these assumptions do not apply. BVS is often used for the determination of attenuation coefficients, dynamic moduli, and especially damping ratios.
BVS was developed primarily to overcome shortcomings in the functional ranges of other viscoelastic characterization techniques. For example, resonant ultrasound spectroscopy (RUS), another popular technique for studying viscoelastic solids, experiences difficulty in determining a material's parameters below its resonant frequency. Furthermore, BVS is less sensitive to sample preparation than RUS.