A 1400‐kg five‐mode bar detector has been constructed and tested at room temperature. Detailed calculations and computer simulations have been performed to optimize the design and study the dynamics of the system. The tests have confirmed the analytical prediction that a large fraction (67% in this experiment) of the energy deposited into the bar is transferred to the last resonator. The rise time of the energy at the last resonator is short (&bartil;2 ms), and corresponds to an effective detector bandwidth of &bartil;500 Hz.