A combination amplifier, in particular a Doherty amplifier allowing dynamic biasing, is provided, the combination amplifier comprising a first amplifier (3,3a,3b) having a first input terminal (11,11a,11b) and a first output terminal (25,25a,25b); a second amplifier (5,5a,5b) having a second input terminal (27,27a,27b) and a second output terminal (29,29a,29b); a first impedance inverter (Li, 43b) connected between the first input terminal and the second input terminal; and an envelope detector (33,33a,33b) comprising a detector output terminal and a detector input terminal which is connected to the first output terminal.