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A new class of bandpass filters with quasi-elliptic frequency response, small physical size, and effective quality factors 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 ) than the electromechanical coupling coefficient of conventional acoustic wave (AW) resonator filters that exhibit FBWs between 0.4-0.8 . In addition, they exhibit 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 loss below 1.25 dB (i.e., in the range of 1525-5150) are demonstrated. Second-order bandpass filters (two poles and four zeros) with 0.24% FBW and less than 1.15 dB of insertion loss (i.e., of 4000) are also shown to improve the passband selectivity and out-of-band rejection. These filters feature dynamic stopband characteristics by tuning the position of their transmission zeros. The operating principle, theoretical analysis, and design guidelines of the AWLR module, as well as a comparison with traditional all-AW ladder-type filters, are also reported. An original and rather simple -circuit equivalent of AW resonators that facilitates the incorporation of spurious modes into a simple Butterworth-Van-Dyke model for a more accurate synthesis of AWLR-based filters is extracted from measured two-port S-parameters.Index Terms-Acoustic wave (AW) filter, bandpass filter, enhancement, RF filter, surface acoustic wave (SAW) filter, SAW resonator, tunable filter.