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I need help with reading piano pieces with key signatures that have sharps or flats (other than C Major or A Minor). I learnt to sight read music using intervals (but do have a very good grasp on recognising note letter names at random as well, I use this when the intervals are too large). However, when I am going through a piece of music reading 2nds, 3rds, 4ths etc., I always miss playing the sharp or flat that should be played in that key (I play the natural instead).
I am tired of websites asking me to memorise the order of flats/ sharps and key signatures - I have done this already and am quite comfortable with it. I even practice scales and play them comfortably. The problem starts when I read music using intervals and miss playing accidentals of the key I am in.
I want to understand how does one develop a mental technique for this? I thought of the following:
1) Remember the lines and spaces while sight reading that need to be sharp or flat in a key : for e.g., for G Major, remember that the 4th line bass, 1st space treble and 5th line treble needs to be sharp. But this technique becomes very very very cumbersome even for two sharp/ two flat key signatures. Moreover, it interrupts sight reading by intervals a lot (you are constantly worried about the letter names).
2) Get familiar with the keys of the scale of the key signature in question on the piano, so that your hands "automatically" go to the black key when there is one. However, while sight reading, this would mean you still need to be "mentally aware" of where your fingers are on the piano and so you know that the moment you come near an F, you need to play F# instead. But doesn't this mean you are still focussing on the letter names while sight reading and not intervals?
I am unable to help the problem with either of the two approaches above. Any other suggestions? How did you guys do it and make playing accidentals in key signatures second nature as pianists say?! Please help !