about 12 decibels, which all but removes them, making them 94% quieter.

This "conversion" from decibel to per cent is more than ridiculous.

It was a collaboration with the company. They probably helped fund it for exclusive licensing to start.

The gardener in my last apartment replaced all of his powertools (mower, blower, trimmer, …) with electric ones powered by an accu-pack he carries on his back. This is an absolute game-changer! I could actually sit outside again and even do stuff for work, when he was there.

This thing influence how air moves through it, so it would make electrics more silent too

Pretty sure when I saw the original post talking about the design, they said the students were only working with electric leaf blowers. So this was designed to make electric leaf blowers even quieter.

"Electric leaf blowers are already far quieter than their gas-powered peers, but they still aren’t the kind of thing you’d like to hear first-thing on a Saturday morning. Looking to improve on the situation, a group of students from Johns Hopkins University have successfully designed a 3D printed add-on that manages to significantly reduce the noise generated by a modern electric leaf blower without compromising the amount of air it’s able to move."

First two sentences of the article.

I don't know mate, I wouldn't replace my electric tools–drills, grinders, saw... with gas ones. But these outdoors tools are a different kind of beast. I've only used an electric chainsaw and it was an absolute crap, maybe there are better ones but it was crappier than the smallest and shittiest gas chainsaws I've used, and a cord around you in that setting isn't great either.

I get what you're saying, but leaf blowers are also commonly used for cleaning up extra grass clippings from the roads, etc.

To blow leaves.

Now pretend your electric blower is actually a super loud and inefficient two stroke motor.

The movement of air isn't noisy, the motor is.

??