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How could I amplify a heartbeat for kids to hear quickly and easily, with or without a stethoscope? Answered

Hi Everyone. Can any of you devise a way to amplify kids' heartbeats so that they are easily heard, without resorting to a stethoscope? Our school is having a fitness night...I thought it would be great to let each kid listen to his heart beat before and after jump-roping, but a single stethoscope would be too cumbersome to use-the kids don't have any experience with them...whereas holding up some kind of mic to their heart would be fun and fast. A quick amplified heartbeat would be best...either through a stethoscope or some other microphone arrangement. Any ideas? Thanks!


I would say: adapt a stethoscope onto a mic without the steth. tube, becaause the stet. is best designed for being a device that detects such sound, unlike the mic in original form which would pick up more aerially-reverberating sounds. i'd get a mic, clay for kids that can be baked in a home oven, gorilla glue - its foaming action can be used to seal from sound the joining of the stethoscope head to the mic, but the same leavening could ruin something else if all is in place already, so be careful. then they could hold the stethosope headed micr to their chest or left breast ribs

Kipkay made a how to convert a stethescope to digital -- very easy, and relatively cheap

Goto a pharmacy, and get a steth for about 10-20 dollars, and a pair of uuber cheap electret microphones from the dollar store (a few dollars) -- after a little wiring/soldering you've got a mic that can plug into a laptop and play out of speakers for everyone to hear.

hi! can you send me mos specification to built it, please?

My old tape deck's dynamic microphones have a cupped end, making them perfect stethoscopes. Listening to a cat's purr amplified to fill a room is an odd sensation, especially with a good subwoofer....


7 years ago

For really quick, how about off-the shelf:

-Laptop (or desktop CPU, particularly on a media cart)

Basically use a laptop to handle all the work. Plug in the mic, hook up the speakers, pull up the volume mixer and ensure the microphone input is "on". Maybe adapt the mic head to something more appropriate for body-contact, attach to a stethoscope head / tubing.

With a fairly mobile CPU, probably won't need to invent much.

BTW- with some sound visualization / editing software you could also visualize the beats. Maybe even print out quick screen grabs of the wave forms...

Would make a nice Instructable, this class-room activity and your solution to your question. Love to see it if you have time to document.

I'd do what Sean suggests, only I'd put a microphone where he puts the drinking straw.


a drinking straw with a small funnel attached might do the trick. However, in this day and age, you'd need to make sure the kids can't poke out their ear drums too, or you may be facing "unexpected negative legal ramifications" from your otherwise altruistic and commendably teacher-like idea.