The invention relates to an amplifier capable of producing a plurality of currents at its output terminals, these currents being controlled by a plurality of input voltages. A multiple-input and multiple-output amplifier of the invention includes 4 signal input terminals, 4 signal output terminals, 4 active sub-circuits and a feedback network. Each active sub-circuit has a sub-circuit input terminal connected to one of the signal input terminals, a sub-circuit output terminal connected to one of the signal output terminals and a sub-circuit common terminal. The feedback network has terminals connected to the sub-circuit common terminal of each active sub-circuit. The feedback network presents, in a known frequency band, an impedance matrix producing a negative feedback such that the transfer admittance matrix of the multiple-input and multiple-output amplifier approximates a given admittance matrix.