Acoustic wave filter devices are disclosed. A device includes a layer providing or on a topmost layer of an acoustic reflector. The intermediary layer has a first region and a second region. The first region has a first layer thickness and the second region has a second layer thickness different from the first layer thickness. The device includes a first multilayer stack on the first region and a second multilayer stack on the second region of the intermediary layer. Each of the first and the second stacks includes a piezoelectric layer on a counter electrode that is located on the respective region, an input and an output electrode. Application of a radio frequency voltage between the input electrode and the counter electrode layer of the first stack creates acoustic resonance modes in the piezoelectric layer between the input and output electrodes of the first and the second stack.