This sample, written by Matt Gruskin, is a frequency modulation synthesizer that uses DirectX and System.Windows.Forms.  The readme.htm in the download (download page: IronPython-1.0-Samples-FMsynth.zip) will get you started.

In the FMSynth UI you can quickly generate tones by clicking on the provided piano keyboard or take more control by specifying a precise frequency and wave type.  You can combine several carrier and modulator wave forms together to form more complex musical sounds and effects.  You can save your “synth” in an XML file.  FMSynth also comes with several sample synth files in the “synths” subfolder which you can load and experiment with.