Decibel Scale | Mechanical waves and sound | Physics | Khan Academy

We often use this logarithmic scale to describe the intensity of sound. Created by David SantoPietro.

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[CliveReyes]

I am 31 years old with BSc. in electronics engineering and 8+ years of experience in wireless communications and this is truly the most brief and beautiful explanation of decibels I have ever come across.

[ellaboons]

this video is amazing. absolutely amazing. I finally understand the whole decibel thing

[MrLegoBLACK]

I swear only if i had a teacher as good as this guy in delivering the information i woldnt have needed to study

[Maha-nxfd]

IDK how i'd be able to pass all these years without khan academy and youtube!
you're awesome <3

[lauelibre]

hahaha i wish you had taught me logs 5 years ago when i learnt them, this is so great

[kebabhue]

Thank you! I'm in medicine and looking at ENT right now. Had some problem with understanding the dB concept but also liking physics from back in the day I now get it!

[kbnumber]

2020 and still listening. First time I really understood decibels.

[soundtech]

I love the nerd-like joking around and the brilliant explanation of how Log works, finally understood it, you're the man!

[nikismile]

you are an outstanding teacher, respect !

[shivensaini]

Hands down, this is the best ever*10^100 definition of decibel I heard so far.

[hyangsookhaleyjoe]

An Audiology student brushing up on logarithm here. Wanted to clarify one thing: loudness is not the same as intensity. Intensity is the physical magnitude of sound pressure but loudness is perceived intensity. So the same intensity can have different loudness magnitude depending on individual. Other than that, it's very helpful! Thank you!!

[thokozanimsimanga]

Awesome staff...You are talented mate.

[lumusic]

Awesome, thank you for the explanation, very easy to understand !

[andreasdekrout]

A very good explanaition.
Just one little thing, that might get overlooked. dB is a relative measure (like octaves in music). Only by using a fixed base value (here you use the "smallest hearable loudness") it becomes an absolute measure (like, how many notes is a tone higher or lower).

[Ayush-bkrv]

This might be the first time, I understood a concept in just a single watch

[ThefamousMrcroissant]

Such a friendly approach to explaining dB. Motivated teacher, funny and great analogies. Just a really, really well done explanation overall.

[saikiran]

made it so easy, I was struggling with it... thank you

[dijonstreak]

...by far...thee best, clearest, simple well-defined explanation i have EVER encountered...i DEFINITELY got ...finally ...thank you SO much....!!

[kevingutierrez]

I'm glad I've finally understand dB, after tens of videos and explanations!

[Govnaa]

Honestly the way you explain this is absolutely incredible.