I love podcasts and audiobooks. They trump radio since I can listen to them anytime I like, fast forward past ads and share them with friends. Librivox provides hours of free entertainment courtesy of the classics. Yes, this means that Voltaire's Candide is ready at 6am on a Saturday while repainting a bedroom!
I don't have a car, by choice. My neighborhood has stores nearby and bus lines that make it perfect for walking or public transit. Ever since I can remember, I've loved to take long walks around my neighborhood and explore the world at a human pace. Portable audio was the perfect match! The side streets are quiet, with minimal car traffic. However, I still need to filter out the noise around me especially on buses, the metro and noisy sidewalks next to busy streets. Cranking up the volume is one option, but not healthy for ears that need to last a lifetime.
A few years ago, I discovered Koss Plug headphones that insert an expanding foam plug within the ear canal, like the safety earplugs I used when mowing lawns. The first time I tried them out, they fit perfectly into my ear and blotted out even the loudest noises. Rumbling city buses and poorly tuned cars no longer interrupted my news feeds, science articles and audiobooks.
The plugs performed well for the first five or six times, but changed their resilience over time. The slow recovery property or memory of the foam seemed to fade, so it became harder to position them inside my ear at the depth required to block sound. They seemed to lose springiness too. If I turned my head, one edge of the foam edge would deform and block the center channel, silencing one of my ears until the foam spring back. During winter, the edges of my hat or hood covering my ears would would have the same effect, tilting the plug inside my ear and blocking the channel. Plus, the plugs would eventually get dirty from earwax - yuck!
I remembered further back to a pair of silicone earplugs, EarPlanes, that worked much better than the foam safety earplugs. They were made from a hollow silicone tube with a cylindrical portion on one end and flanges at the other. The central channel had a ceramic element for equalizing air pressure. The directions suggest placing the flanges inside the ear canal, but they worked better by using the other tapered cylindrical end.
Maybe someone had already combined these ideas together. Jabra headsets come close, but don't place the silicone tube far enough in the ear. Other instructables teaches how to modify earplugs with the same expanding earplug foam as the Koss design.
Since the silicone material in EarPlanes doesn't compress, they wouldn't deform and close up when I turned my head or wore a hat. A search for silicone ear plugs turned up many designs for earbuds described as "in-ear," but they don't extend far enough into the ear to block sound adequately. Plus, it seems that my ears are smaller than most of the designs out there, so they keep falling out.
OK, enough yakking! Time to make earplugs!
remove ink tubes from pens
tape ink tubes to container
apply silicone to ink tubes
remove cured silicone tubes
trim silicone tubes
Step 1: Collect Supplies
You'll need at least 24 hours to complete this project, and 1 hour of active effort.
###### materials ######
$10 - Koss Plug ear buds / headphones
$5 - silicone rubber adhesive
$3 - caulk gun
$1 - 4x ballpoint pens (bic works great)
$1 - tape
container (soda can, plastic yogurt tub or coffee can)
Leftover silicone adhesive will be enough, you won't need a full tube. Some stores sell smaller tubes shaped like a toothpaste tube, so you can skip the caulk gun. the ballpoint pens are only used as templates for forming the inner channel of the silicone tubes, so you can keep using them after this project.
Step 2: Remove Plugs and Ink Tubes
Detach the foam plugs from your headphones. Disassemble the pens to get the ink tubes. These will become templates for silicone tubes to form the in-ear parts.
Step 3: Tape Ink Tubes to Container
Tape the ink tubes over the edge of your container, with the ballpoint edges facing inwards. You'll need at least 4 to make tubes of different diameters to make sure that one of them fits your ear.
Step 4: Apply Silicone to Ink Tubes
This step surrounds the ink tubes with silicone caulk to form a hollow silicone tube. When the caulk cures, you will remove it from the ink tube to leave a hollow silicone tube.
While holding the container, insert an ink tube into the nozzle of the silicone caulk tube. Squeeze the caulk dispenser to apply caulk in an even shape along the ink tube. Taper the caulk along each ink tube, so you'll have a variety of diameters to pick from when trimming the silicone tube. It's important to do this in a single step, to keep the outer surface of the caulk smooth. Also, try to keep the ink tube in the center of the caulk so that the channel is concentric with the outer edges.
Silicone caulk takes about 24 hours to cure properly. As it cures from the outer surface to the inside, you might be tempted to remove it from the ink tubes prematurely. Wait at least a full 24 hours before moving on to the next step, since uncured silicone contacting the ink tubes needs to cure completely to form the inner channel wall.
I tried other templates to make the inner channel like metal coat hangers, but they adhered too well to the cured silicone adhesive and wouldn't detach to form a channel. Other plastic threads might work like an insulated wire, coffee stirrer, grass trimmer cord.
Step 5: Remove Cured Silicone Tubes and Trim
After the caulk cures, remove it from the ink tubes. Twisting the ink tube within the silicone tube seemed to help detach it from the silicone.
Find the ideal diameter of the silicone tube that fits your ear. Start from the narrow end of the silicone tube and trim bits off until you have snug fit. Then cut the other side of the tube to leave a section a bit longer than the Koss plug. Leave a long enough tube to prevent it from lodging in your ear if it detaches from the base speaker.
Repeat this process for your other ear. Taper the ear-end of each tube to make it easier to insert.
Enjoy your new earplugs, see you on the road!