Jazz Pianists - Key Fluency is Good

 
      WOULDN'T IT BE NICE IF IT WEREN'T TRUE .... BUT
 Jazz pianists need to play in all 12 keys - period.   If for no other reason, vocalists will be very specific about keys of songs - some have a relatively narrow range, and only one key will work for a given song, so you'd better be able to deal with it.  By ear, that is.  Other reasons might include being called to play in a Country band, where everything tends to be in A and E, or B, or an Irish band where everything tends to be in D, G and A.  Maybe you'll be playing old stocker big band charts which tend to be in Ab, Eb and Db and Gb.  Or maybe you'll work with a singer-songwriter-guitarist who has no hesitation about slapping on a Capo and playing in any of the 12 keys.   In the Jazz world, tunes tend to be in F, Bb and Eb ( good saxophone keys).   And an even more important reason, is that music itself tends to cycle through different keys within the song, a section here in one key, a section there in another, even though there is no official change of key signature.  And it's pretty handy to be able to comfortably navigate key modulations on a whim.
   So here's a way to start becoming more comfortable with all 12 keys.  First of all, remember that the keys that ARE comfortable are that way simply because we play more in those keys than the others and our visualization skills have had time to become intuitive, while we just feel clumsy and calculating in other keys. The strategy is simply to play in other keys a lot, listen and observe, to make friends with the key.
   The first 8 bar section of When I Take My Sugar to Tea happens to include a plethora of harmonic challenges that, through practice,  will go a long way to producing a greater 12-key comfort level.  This chord progression is taken from the original tune and enhanced a bit to help get us in the habit of using non-root bottom notes in the bass progression and give us a bit of interesting harmonic sophistication to the arrangement. ( As did the early recorded versions, unlike the fake-book versions which are grossly simplified ).

Just in the first 8 bars you will be hearing and playing and develop skills in these areas, and in all keys as you move the progression chromatically:

    ii  - V7  - I     in Major
      iim7(b5)  -  V7  -  i    in Minor
         min7(b5) chord   voiced with the b5 on the bottom
            passing  Diminished Seventh chords
             major chord  voiced with the 5th on the bottom
                 dominant 7th chord voiced with 5th on the bottom
                     Tritone  Substitution     ( Db7 in place of the phantom G7 )
                         Secondary Dominant7 Chord     ( A7 leading to the iim7 chord)
                              b9 inner motion and resolution

At the end of the 8 bars simply ( well, it's not so simple...)  play it over again a half step higher retaining all the nuances that are spelled out in the leadsheet.   I realize this is advanced for many people so I include a simpler version below that would be a good stepping stone to  work up to the first version.
   This tune can be played in any style - open voicings, closed voicings, stride, lounge-lizard arpeggio, rubato ballad,  as long as you use good voicings, making sense of the bottom-note progressing and good voice-leading. 
  But first, listen to the tune:
( note the catchy descending chromatic harmony right after the vocal chorus... )
     Jack Albin and His Pennsylvania Orchestra performing When I Take My sugar To Tea:

 

   Notation in RED is the same thing up a half step.  Go up a half step every time until you get comfortable in all keys.   Hang out in the awkward keys a little longer and get to know it.

 And here is a simpler version to get started on the project -
       This will cultivate familiarity in 12 keys with:

          I  -  V7 progression
             iv   Minor chord     ( a simplified version of iim7(b5)  )
                  Secondary Dominant  VI 7   chord   ( A7 )