The objective of this study was to compare the auscultatory findings using traditional and electronic sensor-based stethoscopes. Thirty-three adult healthy Beagles (20 females, 13 males, mean age: 4.8 years, range 1.4–8 years) were auscultated by four investigators with different experiences (INVEST-1, -2, -3 and -4) independently with both stethoscopes. Final cardiological diagnoses were established by echocardiography. Mitral murmurs were heard with both stethoscopes by all investigators and echocardiography revealed mild mitral valve insufficiency in 7 dogs (21%, 4 females, 3 males). The statistical sensitivity (Se) in recognising cardiac murmurs proved to be 82% using the traditional stethoscope and 75% using the electronic one in the mean of the four examiners, whilst statistical specificity (Sp) was 99% by the traditional and 100% by the electronic stethoscope. The means of the auscultatory sensitivity differences between the two stethoscopes were 0.36 on the left and 0.59 on the right hemithorax, demonstrating an advantage for the electronic stethoscope being more obvious above the right hemithorax (P = 0.0340). The electronic stethoscope proved to be superior to the traditional one in excluding cardiac murmurs and especially in auscultation over the right hemithorax. Mitral valve disease was relatively common in this clinically healthy research Beagle population.