Sound Genration Software-VB 6.0

I have some list of the frequencies and i want to build the musical software that generates the sine wave for each frequencies and plays it. The input for the frequencies will be .xls file in which i will mention the frequencies in line in one column for e.g. 240.12 252.33 360.15 etc... The above frequencies are in Hz I'd like to be able to set the time duration(in the text box) for how long each note in the file is played for, i.e. all note are played for 120 seconds, etc.... The playing of the sound should be continues, for e.g. when i press Play button it starts to play 240.12 for 120 second, then 252.33 for 120 second and then 360.15 for 120 sec until the end of the list, i.e until the blank cell comes for a specified columns. what would be advantageous the i can define duration in the .xls file in the next column for each frequency There should be stop button while frequencies playing, to interrupt the execution. The sound quality should be very good,pure and no any other humming or any other disturbances present. The source code should be available to me for checking the code.