The invention relates to a filter arrangement for a demodulated quadrature amplitude modulated (QAM) signal comprising a first channel (17I) for a cosinusoidale demodulated component of the QAM signal, a second channel (17Q) for a sinusoidal demodulated component of the QAM signal, a filter circuit (10', 10'') which receives two said signal components and has a transmission function for each signal component. The transmission function is comprised of terms which are in-phase with said signal component and out-of-phase with said signal component by π/2 and/or -π/2. The filter circuit is comprised of a cross arm (9) for tapping the out-of-phase terms of the transmission function corresponding to the portions of the signal from the other respective channel. In order to produce a filter arrangement requiring less circuitry and to integrate a semiconductor substrate onto a smaller surface, an inventive circuit configuration (19, 21; 19, 23) is provided. In a first mode, said circuit configuration connects the input of the cross arm (9) to the first channel (17I) and the output thereof to the second channel (17Q). In a second mode, said circuit configuration connects the input of the cross arm (9) to the second channel (17Q) and the output thereof to the first channel (17I). In addition, a suited slope detector is specially provided for use with said filtering arrangement.