When tools like the stethoscope and electrocardiogram are appropriated for use beyond their intended purpose – for example in music and dance performance – how does the training of foreign users shift the framing of sound, and therefore what types of sounds from the body and apparatus come to be analysed or considered? Can we qualify the difference between a doctor and a composer listening to the heart through a stethoscope? How do the motives and methods of practitioners inform what they hear, and how they touch – to the exclusion of sensory processes beyond their frame of reference? As a choreographer and composer working with heart rate sensors, we do not seek to reveal or represent the invisible workings of the heart. Rather, in our performances and installations, the sonification and haptification of heart rhythms – along with the noise produced by the apparatus and its use – are a means to compose a context for intimate listening and touch between performers and visitors at the edges of appropriateness.