A hydraulic system having a load sensing capability with a high pressure cut-off either operational or bypass is disclosed. The hydraulic system includes a pump having variable displacement under control of a pump control signal, a signal duplicator, at least one pressure relief device operable in cooperation with the signal duplicator, and at least one working element driven by the pump. The system includes a high pressure cut-off selector operable in a first mode to allow the signal duplicator to provide the control signal, and in another mode to allow a true signal to control the pump. The system includes a differential relief valve operable to prevent relief flow therethrough when the signal duplicator pressure exceeds the pump output pressure, and to allow relief flow therethrough when pump pressure exceeds the signal duplicator pressure, such that a load sensing capability is maintained under high pump pressure conditions using either the duplicator signal or the true signal for pump control.