The paper presents the results of a comparative analysis of machinability and dynamic stability when turning a nickel-based superalloy with whisker reinforced alumina (WRA) tools in a conventional and prototype toolholders. The use of the prototype toolholder with a spatial structure is shown to significantly suppress vibrations during the machining and stabilize the process within the cutting speed range between 200 and 400 m/min. The above mentioned benefits are demonstrated to be owing to damping properties of the proposed toolholder.