"Perceptions in C" is a submission for the ICAD2004 Concert of Sonifications and was composed as a first experiment by us in the field of converting data to music. Our principle objective was to see if the ECG data (or part thereof) could be made at all "listenable" from a musical standpoint. Central to the data processing approach was the use of a colour note organ to directly interpret the plotted signals as sound. Discretizing the signal values to correspond to frequencies in the equaltempered scale was our attempt to make the data sound musical. Some audio post-processing was used to improve discernment between different channels of data. We feel that in addition to being somewhat musical, the pitch of the resulting sounds effectively represents the general signal trends in the selected data.