Playing intensifying sound

Question

Hello all,

I want a very lightweight sound (some kind of beep) that intensifies in playritme when a parameter gets closser to 0.
The sound doesn't have to change in volume, just play faster and faster between 2 intervals (the same beep).

Which kind of sound file is best for this purpose in C#? mp3, wav, ...?
The sound is best very lightweight so it plays fast whitout to much processor load.

Also what is best for performance playing?
The build in SoundPlayer class or Windows API calls?

Any suggestions for best approach?

Thanks.