A design of the looped-tube thermoacoustic cooling system with an insertion of rubber membrane is proposed. When the membrane to block mass flow due to acoustic streaming is located at a position different from a sound pressure loop, the membrane changes the distribution of the phase difference between pressure and particle velocity. This accompanies the phase difference change in the stack of the prime mover. Since efficient energy conversion is attained when the pressure and particle velocity are in phase, the prime mover of this experiment is shifted to a new in-phase position. Then, collaborating with the enhanced sound intensity due to mass flow blocking, the energy conversion efficiency is significantly enhanced and a high cooling quality is attained.