What is the happiest key? 

Could it be that D, Db, and C Major are most used because those notes are the most common in the vocal range for talking? When songwriters are messing around with an idea or trying to put lyrics to melody, often they will talk it out or mumble/hum whatever comes to mind. It is far easier to start where it is comfortable instead of on a much higher or lower note than the normal talking range. When you come up with an idea perhaps you go from there and realize your song leads to the key of __ or perhaps you do the opposite and build your song around one of the keys of normalcy.

In my opinion, G is the happiest key, followed by F, D, A, C and E.

I think what you said regarding your answer is very interesting and I've thought about it that way too. I think about these questions literally all the time now regarding keys and if there's any inherent emotional significance each one. D would make sense in its popularity when we think in terms of piano and guitar (white keys and easy open chord strumming), I've also sometimes thought that D is like the "real" home of guitar and not E, cuz of DADGAD tuning, it makes the guitar sound much fuller and more resonant no matter how good or bad the guitar is, something very reassuring about it. Maybe C is too low or too bright depending on the register it's played in which makes D the perfect compromise point between warm and bright? I really dunno, and certainly don't want to think of it that way just because of the fact that yeah, it's an overplayed key.

You’re like my second Adam Neely and I love your videos man 👍🏻

A major key is the happiest key. Facts, not opinions.

Why D-flat? They downtune their guitars a half-step, then follow a D major progression.

This video is fantastic! Keep up the great work!

Great research, you deserve more subs!

G major.

i think the happiest keys are d major, a major and e major

A flat major is the happiest key

A major is the happiest key for me.

I find A major and F sharp dorian to be the happiest keys.

Um...I've taken a stats class....three of them to be exact. Frequency tables cannot tell us any significance. They are simply a way of describing data, but it doesn't tell us anything stastically.

For me is F Major

Why is don’t stop me now under D major? Isn’t it in F?

Ab Minor is the happiest

Andy, excellent research. I wanna say, Adam Neely was wrong about his video. And the answer is in your own words. Frequency "spectrum." Spectrum and octaves and harmony---these words all imply color and NUMBER by nature (there are 12 colors in the color-wheel just as there as 12 notes from C to shining sea). Red begins the spectrum at middle C, just as the rainbow begins with red. The different characters of the notes can actually be HEARD, and this implies it's own scientific analysis--but that we all want to avoid. We want to avoid it because it would cause a paradigm shift in our modernist thinking. It would shatter our conception and world-view of sound and contemporary musical culture itself. There is a REASON that fledgling piano tuners keep trying to get the twang out of the F-sharps. Sooner or later, they begin to realize that is the weird wobbly instability of F# is the actually essence of that frequency. With observation, most anyone can hear this. But we avoid it. We avoid it in music conservatories. We avoid it in piano lessons. We avoid it in our language. Art and even poetry are currently banished from science. I already knew that D is the most cheery, up-beat key because i learned to hear it, but also i saw it in Classical music (and Bach, Mozart, Beethoven, Chopin---these guys already knew the answers to key psychology). For an example of the topic here (D-major), you can hear it in Hayden's Symphony no. 6, the "Sunrise Symphony." If C is red, then D shifts up to Orange. Orange is the fiery but gentle, warm ascension of the sun unto the day. What could be happier than watching the night break open to light? In the words of filmmaker David Lynch, "The sun, without even trying, removes the darkness." It's just awesome that you figured this out by comparative analysis. In popular music i could add Perry Como's almost embarassingly innocent "Magic Moments" and Erasure's "Waiting for the Day." Even in the lyrics, Waiting-for-the-Day reads "You can be my lifelong friend. You can be the light of dawn. You can keep me close at hand. You can keep me safe and warm. // I will be your fantasy, If you come and stay with me. I will try to give you all, Waiting for the night to fall." Incredibly, Neely mocks the Schumann Doctrine, even as he holds it in his very hands. With a few minor changes i'd make, the Classic Schumann Doctrine actually has ALL of the answers to key-psychology already spelled out. The scientist who throws the baby out with the bath water will never grow up.

that isnt the answer, the answer is *g-half-sharp*

you trying too hard to be vsauce