Calculate a variable in an array

YESSS! Problem SOLVED!
Thank you so much for your help.

I finally ended up with this code and it works flawlessly.

//Roland Jv-1010 Scale Controller.
#include <MIDI.h>
#include <midi_Defs.h>
#include <midi_Message.h>
#include <midi_Namespace.h>
#include <midi_Settings.h>
MIDI_CREATE_DEFAULT_INSTANCE();

//Scale ON/OFF Arrays
byte onArray[12] = {0xf0, 0x41, 0x10, 0x6a, 0x12, 0x00, 0x00, 0x00, 0x07, 0x01, 0x78, 0xf7}; // ON array
byte offArray[12] = {0xf0, 0x41, 0x10, 0x6a, 0x12, 0x00, 0x00, 0x00, 0x07, 0x00, 0x79, 0xf7}; // OFF array

byte SA[22] = {0xf0, 0x41, 0x10, 0x42, 0x12, 0x40, 0x11, 0x40, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xf7};

// Analog pin A0-ON
int switchPinON = 14;
// Analog pin A1-OFF
int switchPinOFF = 15;
// Analog pin A2-SEND
int scaleSend = 16;


int Do = 2;
int Dos = 3;
int Re = 4;
int Res = 5;
int Mi = 6;
int Fa = 7;
int Fas = 8;
int Sol = 9;
int Sols = 10;
int La = 11;
int Las = 12;
int Si = 13;


void setup() {
  MIDI.begin();                            //Midi channel = 1 , Baud = 31250
  pinMode (switchPinON, INPUT);           //Scale ON
  pinMode (switchPinOFF, INPUT);         //Sclae OFF
  pinMode (scaleSend, INPUT);           //Scale SEND
  pinMode (Do, INPUT);
  pinMode (Dos, INPUT);
  pinMode (Re, INPUT);
  pinMode (Res, INPUT);
  pinMode (Mi, INPUT);
  pinMode (Fa, INPUT);
  pinMode (Fas, INPUT);
  pinMode (Sol, INPUT);
  pinMode (Sols, INPUT);
  pinMode (La, INPUT);
  pinMode (Las, INPUT);
  pinMode (Si, INPUT);
}

void loop() {

  // ARRAY VALUES
  if (digitalRead(scaleSend) == HIGH)
  {
    MIDI.sendSysEx(22, SA, true);
    delay(1000);
  }
  if (digitalRead(switchPinON) == HIGH)
  {
    MIDI.sendSysEx(12, onArray, true);
    delay(1000);
  }
  if (digitalRead(switchPinOFF) == HIGH)
  {
    MIDI.sendSysEx(12 , offArray, true);
    delay(1000);
  }

  // 12 ON/OFF Switches.
  // ***************************************  DO

  if (digitalRead(Do) == HIGH)
  {
    SA[8] = 0x0e;
  }
  else
  {
    SA[8] = 0x40;
  }
  // ***************************************  DO#
  if (digitalRead(Dos) == HIGH)
  {
    SA[9] = 0x0e;
  }
  else
  {
    SA[9] = 0x40;
  }
  // ***************************************  RE
  if (digitalRead(Re) == HIGH)
  {
    SA[10] = 0x0e;
  }
  else
  {
    SA[10] = 0x40;
  }
  // ***************************************  RE#
  if (digitalRead(Res) == HIGH)
  {
    SA[11] = 0x0e;
  }
  else
  {
    SA[11] = 0x40;
  }
  // ***************************************  MI
  if (digitalRead(Mi) == HIGH)
  {
    SA[12] = 0x0e;
  }
  else
  {
    SA[12] = 0x40;
  }
  // ***************************************  FA
  if (digitalRead(Fa) == HIGH)
  {
    SA[13] = 0x0e;
  }
  else
  {
    SA[13] = 0x40;
  }
  // ***************************************  FA#
  if (digitalRead(Fas) == HIGH)
  {
    SA[14] = 0x0e;
  }
  else
  {
    SA[14] = 0x40;
  }
  // ***************************************  SOL
  if (digitalRead(Sol) == HIGH)
  {
    SA[15] = 0x0e;
  }
  else
  {
    SA[15] = 0x40;
  }
  // ***************************************  SOL#
  if (digitalRead(Sols) == HIGH)
  {
    SA[16] = 0x0e;
  }
  else
  {
    SA[16] = 0x40;
  }
  // ***************************************  LA
  if (digitalRead(La) == HIGH)
  {
    SA[17] = 0x0e;
  }
  else
  {
    SA[17] = 0x40;
  }
  // ***************************************  LA#
  if (digitalRead(Las) == HIGH)
  {
    SA[18] = 0x0e;
  }
  else
  {
    SA[18] = 0x40;
  }
  // ***************************************  SI
  if (digitalRead(Si) == HIGH)
  {
    SA[19] = 0x0e;
  }
  else
  {
    SA[19] = 0x40;
  }

// ROLAND CHECKSUM

byte partialSum = 0;
for (byte i = 8 ; i <= 19 ; i++)
{
  partialSum += SA[i];
}
{
SA[20] = 0x80 - (partialSum & 0x7F);
}
}