Any precordial tricks?

A foam ear plug with tubing stuck thru it connected to a normal stethoscope bell works in a pinch. Hope this helps.

If you can’t find those nice foam disposable earpieces, and you’re really desperate, gather the following: 14 g IV, nasal cannula, a male to male adapter, and tape. Take the nasal cannula and cut off both ends so you just have the tubing left over. Take the needle out of the 14 g, and cut off most of the catheter so you have only the metal hub and maybe a cm of the catheter left. With all of your might, jam the tubing over the metal of the 14g and tape it together. This is where you can connect the bell. If you don’t have one, you should be able to use the bell of any disposable stethoscope. Shove the male to male adapter in the other side and this is now your ear piece. If you twist it in your ear, it actually works quite nicely, but your ear will surely get sore if you leave it in for a long time. Enjoy!

you can try to make an earpiece with foam tape, just wrap it around until it's about the size of your earcanal.
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