Abstract
"Five-mode" massive aluminum gravitational radiation detectors cooled to millikelvin temperatures are considered for the purpose of approaching quantum sensitivity over a large bandwidth. A five-mode detector with a center frequency at 800 Hz would have a two-sided usable bandwidth of the order of 400 Hz. A five-mode detector with a center frequency at 1660 Hz would have a usable two-sided bandwidth of the order of 1000 Hz.