This thesis deals with femtosecond broadband spectroscopy in the visible regime, which is used to study strongly correlated electron systems. The materials that were studied are high-temperature cuprate superconductors of various dopings and the charge-density wave material tantalum disulfide. Central results comprise the coherent excitation and the detection of a charge fluctuation of the superconducting condensate in optimally doped lanthanum strontium cuprate, the quantification of the electron-phonon coupling in lanthanum cuprate, including the description of a method to directly extract matrix elements from the time-resolved experiments, the observation of spectroscopic evidence for paired electrons far above the superconducting transition temperature in neodymium barium cuprate, and a detailed study of coherent phonons associated with the charge ordering in tantalum disulfide.