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A new class of bandpass filters with quasi-elliptic frequency response, small physical size, and effective quality factors (Qs _eff ) of the order of 1000 are presented. They are based on novel hybrid acoustic-wave-lumped-element resonator (AWLR) modules that enable the realization of bandpass filters with fractional bandwidths (FBWs) that are much larger (0.91-5.1 k _t ² ) than the electromechanical coupling coefficient (k _t ² ) of conventional acoustic wave (AW) resonator filters that exhibit FBWs between 0.4-0.8 k _t ² . In addition, they exhibit Qs _eff that are 25-50 times larger than in traditional lumped-element filter architectures. Quasi-elliptic single-pole bandpass filters (one pole and two zeros) made up of commercially available one-port surface AW resonators and surface-mount-device components are manufactured and measured at 418 MHz. Various passbands with FBW between 0.07% and 0.4% and insertion …