Stevie Wonder - Songs in the Key of Black

Beginning pianists are often drawn to the white keys. They are orderly, collectively making up a major scale; it's easy to noodle on white keys and come up with something that sounds loosely musical.

But the black keys are not without their charm. Making up a pentatonic scale, they allow young players to play some familiar sounds and melodies without worrying about hitting an off note. Pedagogically it is often preferable to start young students on the black keys, as they are grouped in twos in threes, allowing players to start seeing patterns on the keyboard.

I have a theory that Stevie Wonder was drawn to the black keys from the beginning because of his blindness. To a blind man the white keys are uniform and indistinguishable without noodling for a bit.  But the groupings of the black keys allow him to find his place immediately. Where many pianist/songwriters are drawn to common keys, I feel that Stevie is more comfortable in the deep keys. For example, here are ten famous Elton John songs and their keys:

Your Song - Eb

Goodbye Yellow Brick Road - F/Ab

Tiny Dancer - C

I Guess That's Why They Call It the Blues - C

Saturday Night's Alright - C

Crockodile Rock - G

Bennie & the Jets - G

Someone Saved My Life Tonight - Ab

Can You Feel the Love Tonight - Bb

Daniel - C

Not too adventurous. For contrast, here are the top 12 "frequently mentioned" Stevie songs (according to Google):

I Just Called to Say I Love You - Db, modulates to D and Eb

Superstition - Eb minor

You Are the Sunshine of My Life - C, modulates to Db

For Once in My Life - F, modulates to Gb

Isn't She Lovely - E

Higher Ground - Eb minor

Living for the City - Gb

My Cherie Amour - C, modulates to Db

Boogie on Reggae Woman - Ab

I Was Made to Love Her - F

I Wish - Eb minor

Sir Duke - B

7/12 of them are in what I would call uncommon keys - Gb, B, Db, Eb minor - and those in common keys usually modulate at some point.

Playing in these keys also allows Stevie to do some glissando tricks on the black keys at times. As mentioned, the black keys constitute either an Eb minor pentatonic scale or a Gb Major pentatonic scale. Running your hand up and down the black keys makes for a pretty cool effect, when used well. Stevie uses it on several keyboards for the intro of You Haven't Done Nothing:

It also works well over certain chords, particularly the Ab11 chord. This type of chord is called many different names - sus9, Ab/Gb, 7sus, etc...I like calling it an 11 chord. Its function is typically to act as the V chord, in this case in the key of Db.

In Knocks Me Off My Feet, you hear Stevie go to town on this when the big Ab11 chord sets up the modulation. Check it out around 2:40:

It also works well over a BMajor7 chord, as the black notes turn it into a BMajor13 chord. In Summer Soft, which modulates constantly, you can hear Stevie do this around 3:40:

There is no physical reason one key should have a different sound than others; it all depends on the song. But anecdotally speaking (as a musician) there is a definite warmth to the darker keys. It may just be that they are less cliche, and thus sound more novel. I'm sure the musicians who played with Stevie were pushed out of their comfort zones and probably in to much more explorative areas by having to play in uncommon keys. It is one of the ways that blindness may have contributed to his musical brilliance, by simply giving Stevie a proclivity for the ebony keys.