  In this work we extend low frequency impulsive stimulated Raman
microspectroscopy to the pre-electronic resonance regime. We use a broadband
two color collinear pump probe scheme which can be readily extended to imaging.
We discuss the difficulties unique to this type of measurements in the form of
competing resonant two-photon processes and the means to overcome them. We
successfully reduce the noise which arises due to those competing processes by
eliminating the detected spectral components which do not contribute to the
vibrational signature of the sample though introduce most of the noise.
Finally, we demonstrate low-frequency spectroscopy of crystalline samples under
near-resonant pumping showing both enhancement and spectral modification due to
coupling with the electronic degree of freedom.
