Devices (1,2) comprising feedback-less amplifiers (16,19,26,29) that are gain controlled introduce linear relationships between output signals and input signals of the feedback-less amplifiers (16,19,26,29) by providing the feedback-less amplifiers (16,19,26,29) sub-circuits in the form of first transistors (33) operated in their triode regions for receiving input signals and second sub-circuits in the form of second transistors (34) for receiving control signals and third sub-circuits in the form of resistors (35) for generating output signals, whereby the respective first and second and third sub-circuits form a serial path. Second circuits (4) receive gain signals and convert the gain signals into the control signals. The control signals are copies of the gain signals. The second circuits (4) comprise current sources (6) and third and fourth transistors (41,42). The current sources (6) comprise fifth and sixth transistors (61,62). The second circuits (4) further comprise voltage sources (9) further current sources. Third circuits (8) compensate common mode currents.