this post was submitted on 20 May 2024
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[–] [email protected] 30 points 5 months ago (2 children)

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

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

[–] [email protected] 55 points 5 months ago (2 children)

Why? dB is logarithmic so it's difficult for people to picture how loud something is, if that's the only number given.

[–] [email protected] 19 points 5 months ago (1 children)

And so are our ears. That's why we use db. So 12db is not perceived by us to be 94% quieter.

[–] [email protected] 13 points 5 months ago (1 children)

So its 94% less sound because this seems sound calculated -12db in % with conventional formulas?

How would we describe perceived sound exactly, not many people can imagine something when given a db value? Maybe we should?

[–] [email protected] 2 points 5 months ago (1 children)

When loudness is described there's often lists with examples of things with their typical loudness specified in dB, so you can compare against things you may have heard.

See the image chart here

https://decibelpro.app/blog/decibel-chart-of-common-sound-sources/

[–] [email protected] 3 points 5 months ago

I have done a lil research but what i needed was this site. Great resource, maybe even coolguides material.

[–] [email protected] 5 points 5 months ago* (last edited 5 months ago) (2 children)

Well, 93.7% to be more exact. Did you recalculate it yourself the same i did ?

[–] [email protected] 1 points 5 months ago* (last edited 5 months ago) (2 children)

Your calculation was about energy. But the calculation of energy is next to useless when you are trying to compare two different noises. You need to care about perception.

The perception of noise is quite complicated. But as a rule of thumb: when some noise changes by -10dB, then you hear it about "half as loud".

Source: I have a university degree in acoustics.

So for the reduction of -12dB here, it will be perceived as "nearly half as loud". Very different than the "94%" is suggesting.

[–] [email protected] 0 points 5 months ago

It’s also only 2db overall, the one frequency they dropped that much.

[–] [email protected] -1 points 5 months ago (1 children)

We agree that the -12dB is what's important for human hearing ... Now, you may agree that the 94% reduction is what counts regarding engineering // fabrication // design.

[–] [email protected] 0 points 5 months ago (1 children)

We agree that the -12dB is what's important for human hearing ... Now, you may agree that the 94% reduction is what counts regarding engineering // fabrication // design.

-2db* and 37%*

Why are you perpetuating the wrong information?

[–] [email protected] 1 points 5 months ago (1 children)

The snippet quoted in the original comments and referenced in subsequent comments refers specifically to the decibel reduction of the frequencies being targeted by the invention, not the volume of the overall sound.

[–] [email protected] -1 points 5 months ago

Is it? Because the next sentence in the paragraph (and the only sentence missing in the quote) is the overall sound reduction. Which is far more important and far less misleading than saying 12db and 94% quieter.

Its intentionally misleading to deceive people, and than the general public incorrectly defends it, this is you.

[–] [email protected] 1 points 5 months ago

The team reduced the overall leaf blower noise by about two decibels, making the machine sound 37% quieter.

You omitted the most important data, it’s 2db overall, not 12db.

So your own “recalculation” isn’t even in the right ballpark as the correct answer.

Its people that misinterpret the information and perpetuate it like you are doing here that makes these look far better than they actually are.