Okies, First of all you can't throw away accidentals (ie: make the F a natural). If you do this, that is to say there is an F# in the key sig and you make it a natural in the melody line, that is modulation and therfore a shift in key. Try this, instead of a shift from A Major to C# Major, why not do A Major to Db Major (make the pivot chord Ab7) Sounds EXACTLY the same right! Db Major contains the following FLATS: Bb, Eb, Ab, Db, Gb and Bb, thus leaving the F C completely untouched like you have said above. In the Key of C# Major, the F and C and both sharp, and by making them natural you have then gone out of C# Major and into a key defined by the melody (Bb or Dm perhaps) It is then more feasible to go from the key of Db Major to F Major, It now turns into a natural modulation. Again it sounds exactly the same, but is more naturally executed. Consider your key changes: A Major - C# Major - F Major (You have gone from 3 sharps, to 7 sharps to 1 flat, quite messy and has no structure or reasoning) Consider my key changes: A Major - Db Major - F Major (going from 3 sharps, to 6 flats, to 1 flat, a bit tidier) Although this tritone movement in the first key change makes us shift from sharps to flats, the use of the pivot chord playing the dominant seventh softens the blow (you're example G#7, my example Ab7) Like I said it doesn't sound any different, but it's a lot clearer. C# Major would almost never be used. I guess you're a guitarist, that's why you like the sharps, lol, you wont need to change the way you position you're chords, they are the same sound, it is in effect the same chord, the way you label them is different. Hope this helps