It is presented an amplifier device comprising: a primary amplifier arranged to receive at least part of an input signal; a secondary amplifier arranged to receive at least part of the input signal; a first directional coupler device, wherein one input of the first directional coupler device is connected to the primary amplifier and a second input of the first directional coupler device is connected to the secondary amplifier; and a first multiband termination device arranged to reflect signals with a predetermined reflection phase in at least two frequency bands. One output of the first directional coupler device is a main output of the amplifier device and a second output of the first directional coupler device is connected to the first multiband termination device. A corresponding radio base station and mobile communication terminal are also presented.