Radio frequency filters are disclosed. A bandpass filter is discloses that includes one first bulk acoustic resonator on a first chip including a first piezoelectric layer having an LN-equivalent thickness less than or equal to 535 nm; a second bulk acoustic resonator on a second chip including a second piezoelectric layer having a thickness greater than the LN-equivalent thickness of the piezoelectric layer on the first chip; and a circuit card coupled to the first chip and the second chip and that electrically connects the first chip to the second chip.