Midi Metronome

[Fear the Weasel]

Hi there, I'm building a simple midi based metronome and I'm wondering if anyone knows of a good sound generating circuit to give me a nice clicking sound.  Something that could just be fed with a pulse from a DOUT and ouput at headphone level.  Even better would be if I could have a higher pitched click for the start of each measure (could be fed from another DOUT).  The midibox part is pretty much done and this is all I need to finish it off.  :D

Thanks!