Personally, I know a lot about music, melodies and chords, and I also play the piano. I have to mention that it help me a lot, for example it help me create a nice basseline more easily and faster. But, when I make a sampled beat although it doesn't help me a lot it still helps me. So, you can continue make beats without knowing how to play a music instrument, but if learn it, it will help you in big way.