You may try soundclub: http://www.bluemoon.ee/history/scwin/index.html. The dos version can load midi.

Besides why convert to .mod at max .mod files support 8 tracks.

E.g. take a look at: http://www.roland.com/products/en/VSC-MP1/index.html

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i forgot: http://www.polyhedric.com/software/mn/
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