A mechanical keyboard will always be louder than a membrane keyboard because of their physical characteristics. A membrane keyboard involves a plastic tray with some keyboard sliders striking a rubber membrane to make contact with a circuit board. Mechanical keyboards almost always have a metal plate that holds mechanical switches with springs in them, so even a linear switch that doesn’t click still makes a tapping noise when it bottoms out, and when bottoming out, it can make that metal plate vibrate and make a pinging noise. Here’s how I reduced the pinginess of my mechanical keyboard.
Mechanical keyboard acoustics
Mechanical keyboard enthusiasts go to some interesting lengths to eliminate that ping, and there is an entire sub genre of YouTube videos where keyboard enthusiasts modify their keyboards and show off the resulting acoustics.
I’m not going that far. I just wanted to find an easy way to make my keyboard a bit less pingy and maybe a bit less loud and I found it.
A common method is to buy a foam mat intended for use as a drawer liner. People commonly use them in toolboxes so their tools don’t slide all over the place when they open and close the toolbox drawers. But I decided to try something that I’ve never seen anyone suggest: melamine sponges. These are commonly sold under the Mr Clean Magic Eraser trade name, but there are plenty of generic equivalents available inexpensively. These are sold as a cleaning product, but melamine was originally designed and marketed as a sound proofing product.
So if they can quiet down a recording studio, can they quiet down a keyboard?
Quiet your mechanical keyboard with melamine sponge
I bought a package of thin, extra strength versions of the product. These are about 10 mm tall, where the normal size is usually closer to 20 or 25 mm thick.
My keyboard had about 5 mm of clearance between its PCB and the bottom of the case. The thin sponges were still too thick to fit as-is.
So I cut a sponge in half lengthwise, and then used a utility knife to cut them into two rectangles that were about 5 mm thick. The material has a lot of springiness, so you don’t need a lot of precision. When cutting, be very careful how you are holding the sponge, and make the cutting motion away from your hand and any other part of your body to avoid injury. The material is not difficult to cut, but don’t get in a hurry. I also recommend using a new blade, because it is easier to maintain control of a new blade than a dull blade.
It is tempting to try to cut the sponge into 5mm slices using a pair of scissors, because it seems safer, but I didn’t have any success with that. I ended up shredding the sponge.
Installing the melamine sponge in a keyboard
Once you have a few rectangles of melamine sponge, take your keyboard apart if you haven’t already. Then place pieces of sponge into the open areas. You don’t have to cover all of the open areas. The idea is to reduce the amount of empty air in the body to cut down on echo. What I did was place pieces of sponge in the body to fill as much open area as possible, and then I taped the pieces into place with painters tape. The painters tape mainly serves to keep the pieces from sliding around too much while I put it back together. It doesn’t have to have a very strong bond to do its job.
I ended up using about $2 worth of melamine sponges to fill the voids in a mechanical keyboard with brown switches. After doing so, the keyboard was almost as quiet as an unmodified red switch board. The switches themselves still have a subtle click followed by the sound of the switch bottoming out. But I nearly eliminated the metal ping. I can always open it back up and add a few more pieces to fill in the largest remaining voids. But the remaining pinginess isn’t significant enough for me to feel like it’s worth the bother.
A mechanical keyboard offers better ergonomics and accuracy than membranes. But the tradeoff is noise. If you want a sound profile closer to a membrane board, you really can have it all. Spend about half an hour putting melamine sponges in the body of your keyboard underneath the PCB quiets it down noticeably.
In the end, I found it more effective than using rubber o-rings, and it doesn’t affect the travel of the keys. And it wasn’t any harder than installing o-rings either.
David Farquhar is a computer security professional, entrepreneur, and author. He started his career as a part-time computer technician in 1994, worked his way up to system administrator by 1997, and has specialized in vulnerability management since 2013. He invests in real estate on the side and his hobbies include O gauge trains, baseball cards, and retro computers and video games. A University of Missouri graduate, he holds CISSP and Security+ certifications. He lives in St. Louis with his family.