Syntax help with 2D array

Wrap the whole bank/chord/note assignment into a function and call it in setup(). And park that long-ass function at the end of the sketch.

If you are using the Processing IDE, then you can even put that function into a separate tab.

byte[][] chordBank2 = new byte[8][6];

void setup() {  
  initializeBanks(); 
}

void draw() {  
  int anotherSingleNote = getNote(7,4); // from the 7th chord, get the 4th note
  println(anotherSingleNote);
  stop();
}

int getNote(int chordNum, int noteNum) {
  return chordBank2[chordNum-1][noteNum-1];
}


void initializeBanks() { 
  chordBank2[0] = new byte[] {40, 45, 50, 55, 59, 64}; // open strings
  chordBank2[1] = new byte[] {40, 47, 52, 56, 59, 64}; // E major
  chordBank2[2] = new byte[] {41, 48, 53, 57, 60, 65}; // F major
  chordBank2[3] = new byte[] {43, 47, 50, 55, 59, 67}; // G major
  chordBank2[4] = new byte[] {33, 45, 52, 57, 61, 64}; // A major
  chordBank2[5] = new byte[] {35, 47, 54, 59, 63, 66}; // B major
  chordBank2[6] = new byte[] {36, 48, 52, 55, 60, 64}; // C major
  chordBank2[7] = new byte[] {38, 50, 57, 62, 66, 69}; // D major 
  
  // add all other banks/chords/notes here... 
}