I. Introduction
The stethoscope is an acoustic non-invasive medical device for diagnosis and used to listen internal sounds of the human body[1]. The multi head chest piece of stethoscope contains a bell to pick up lower frequency sound of a heartbeat and a diaphragm of stethoscope for the higher frequency of the sound [2]. This structure able to provide a better sound for transmission because the acoustic of pressure wave travel through the tubing also known as a vacuum tube is develops. The most type of stethoscope used these days is the acoustic stethoscope. However, the problem with this acoustic stethoscope is the sound level is very low. It is hard to analyze the heart sound and difficult to be diagnosed by a medical doctor. This is why several forms of digital electronic stethoscope have been developed to replace the conventional acoustic stethoscope [3].