‘La viole parfaite’ is an article by Toon Moonen published in 1993, in which he describes his method of reconstructing an early viol on the basis of the instrument’s depiction in Raphael’s Saint Cecilia (c.1515–18). To date, the argument for using an iconographic source as a model for a Renaissance viol remains the same: all extant larger bowed stringed instruments dated to before the last quarter of the 16th century have been either so significantly modified that their original state is unrecognizable, or they are obvious counterfeits. This article examines Moonen’s reconstruction method in an interdisciplinary case study. Based on infrared reflectograms, for example, it was possible to show that the viol lying on the ground in Saint Cecilia was not subsequently altered. The reconstruction of the viol’s outline using 3d graphics yields completely new results, and perceptual psychology allows an analysis of the ‘reality effects’ possibly intended by the painter. In addition, this research also enables the examination of the general methodological requirements for reconstructing musical instruments from iconographic sources.