I used the audio extracted from the video below. It was taken by a Logitech 270 webcam which was pressed against my finger, hence the strange red pulsating color.

The audio was truncated as in the beginning the camera was moved a bit harshly and at the end the boiler used by my other self was creating an increasing white noise.

I just used Hjerte 0.3 (available on this page) to classify the heart sound. It recognizes my heart beat quite well, and seems to find convincing S1 and S2 sounds.

What are the take home points?

- There is no need for a ultrasound Doppler to record heart sounds.

- Heart sounds can be recorded on a finger!

- The Hjerte algorithm works even in weird conditions (ordinary microphone, lot of noise).