Stethoscopes have now evolved into advanced electronic systems that offer features such as color spectrographic analysis. Shown here is the electrocardiogram (top), phonocardiogram (middle) and color spectrogram (bottom) obtained from a healthy six-year-old girl with an innocent systolic murmur. S1=first heart sound; S2=second heart sound; SM=systolic murmur. Image used under a Creative Commons Attribution License 4.0 from Sarbandi RR, Doyle JD, Navidbakhsh M, Hassani K, Torabiyan H. A Color Spectrographic Phonocardiography (CSP) applied to the detection and characterization of heart murmurs: preliminary results. Biomed Eng Online. 2011 May 31;10:42. doi: 10.1186/1475-925X-10-42. PubMed PMID: 21627809; PubMed Central PMCID: PMC3126734.