A SIMBOL-X View of Microquasars

Based on spectral simulations, I show how focusing of the X-ray radiations above 10 keV will open a new window for the study of microquasars. With simulations of soft and hard state spectra of Galactic sources, I discuss how SIMBOL-X can help to precisely measure the spin of black holes. Spectral study on short ~1 s time scales will also allow the accretion-ejection connections to be accessed, and the formation of jets possibly witnessed in X-rays. I then turn to external galaxies, and demonstrate that spectral studies of hard sources will be possible up to at least ~1 Mpc. For such sources, subtle spectral signatures (e.g. a reflection bump) will clearly be detected. I finally discuss the implications that these original results will bring on the physics of microquasars and black holes.