Do-it-yourself, Comfortable and Secure Custom Earphones

I’ve not been happy with the results of “noise canceling” headphones. I find that while they do reduce the level of constant noises (like fans, hums, buzzing, etc), they ddon’t completely eliminate it, and the noise cancellation circuitry introduces its own annoying noise impurities. I started researching canal headphones, which sit in your ear canal, rather that in your outer ear. They act like ear plugs, actively blocking outside noise from reaching your ear. source