The calender comprises a predetermined number of rolls and at least one of the rolls, for example, the outer roll or the lowest roll of such predetermined number of rolls is structured as a tubular roll or controlled deflection roll comprising a stationary roll support member or beam and a roll shell which rotates about the stationary roll support member and is supported thereat. A position sensor determines the position of the roll shell which is regulated with respect to predetermined reference values by a regulating device. A pre-selected number of different reference values for the position of the roll shell are provided and by selecting an appropriate one of these reference values there is achieved the result that different numbers of the predetermined number of rolls are operative while the remaining rolls of such predetermined number of rolls bear against related stops so that their related roll nips or gaps remain open.