An in-line resonator filter comprising a linear array of three or more conductors, the linear array comprising: a first pair of adjacent conductors (410, 410) having inductive main coupling and oppositely signed capacitive main coupling; a second pair of non-adjacent conductors (410, 410) having inductive cross-coupling; and one or more tuning elements, each extending from a ground plane of the in-line resonator filter, wherein: the first and second pairs have one conductor (410) in common; between the second pair of non-adjacent conductors, there is no direct ohmic connection that provides the corresponding inductive cross-coupling; and at least a portion of the oppositely signed capacitive main coupling compensates for at least a portion of the inductive main coupling between the first pair of adjacent conductors; characterized in that each conductor comprises: a high-impedance base (412(i)) that is shorted to a bottom ground plane of the in-line resonator filter; and a low-impedance, shaped head (414(i)) that does not contact a top ground plane of the in-line resonator filter, and the shaped heads of two or more conductors are different. a first pair of adjacent conductors (410, 410) having inductive main coupling and oppositely signed capacitive main coupling; a second pair of non-adjacent conductors (410, 410) having inductive cross-coupling; and one or more tuning elements, each extending from a ground plane of the in-line resonator filter, wherein: the first and second pairs have one conductor (410) in common; between the second pair of non-adjacent conductors, there is no direct ohmic connection that provides the corresponding inductive cross-coupling; and at least a portion of the oppositely signed capacitive main coupling compensates for at least a portion of the inductive main coupling between the first pair of adjacent conductors; characterized in that each conductor comprises: a high-impedance base (412(i)) that is shorted to a bottom ground plane of the in-line resonator filter; and a low-impedance, shaped head (414(i)) that does not contact a top ground plane of the in-line resonator filter, and the shaped heads of two or more conductors are different. the first and second pairs have one conductor (410) in common; between the second pair of non-adjacent conductors, there is no direct ohmic connection that provides the corresponding inductive cross-coupling; and at least a portion of the oppositely signed capacitive main coupling compensates for at least a portion of the inductive main coupling between the first pair of adjacent conductors; characterized in that each conductor comprises: a high-impedance base (412(i)) that is shorted to a bottom ground plane of the in-line resonator filter; and a low-impedance, shaped head (414(i)) that does not contact a top ground plane of the in-line resonator filter, and the shaped heads of two or more conductors are different. a high-impedance base (412(i)) that is shorted to a bottom ground plane of the in-line resonator filter; and a low-impedance, shaped head (414(i)) that does not contact a top ground plane of the in-line resonator filter, and the shaped heads of two or more conductors are different.