this is similar to the Tristendo suggest, but with a little changes...
Depend on what your looking for... but this is bassically how "i do it"
i know there is many many other ways to do it, i just like this one and few others. But the best way to improve is with the DMC sample, so far. And you can save some space in the channels for notes . But even with FULLED square/triangle/dpcm KICks, your still able to get a melody. and if is just dance dance music, will be even more esier to do a melody.
Here is the file
http://2a03.free.fr/dl.php?file=2981 (hope this works for you)