Disclosed herein is a radiological instrument (100, 200, 300, 400, 600, 700, 800) comprising at least one pulse shaper circuit (102) configured for a direct conversion radiation detector (108). The at least one pulse shaper circuit comprises an amplifier (110). The pulse shaper further comprises a feedback circuit (118) connected in parallel with the amplifier; a first switching unit (120) connected in series with the feedback circuit; a second switching unit (122) connected in parallel with the amplifier; a discriminator circuit (124) that provides a discriminator signal (128) when the output exceeds a controllable signal threshold; and a control unit (124) for controlling the first switching unit and the second switching unit, wherein the control unit controls the second switching unit such that a substantial part of the signal is integrated, when the second switching unit is closed.