In order to solve the phenomenon of Stokes duration broadening in the process of stimulated Brillouin scattering (SBS) compression, a new interferometric scheme is proposed. For interferometric scheme, the medium density modulation excited by a fixed standing-wave instant of acoustic noise, which fixes generation position of Stokes and solves the problem fundamentally. It is shown theoretically and confirmed experimentally that interferometric scheme can suppress the broadening effectively and obtain sub-phonon lifetime compression.