Each one is easier as more of the artists are in the database. The basic entry is done by using Picard (http://picard.musicbrainz.org/) to copy the metadata out of the recordings and into the website.
So my idea was basically to copy the limitations on an NES sound chip, which has 3 channels that can play notes, a noise channel, and a channel that can play some low quality samples.
So pitched percussion like marimba or timpani would be counted as a note.
There are times in NES music where they would sacrifice a channel to double a sound (usually with delay), but I think for the sake of making interesting arrangements, we can consider unison notes as just one.
Also I think to make things a little less restricted, the 3 note rule doesn't have to apply to the entire arrangement, just the majority of it. So if you want to introduce a solo on top of the arrangement, or fill things out for intros or outros then that will be fine.
Since these limitations are based around what NES hardware can do, any cover that uses the same arrangement from an NES tune will automatically qualify. I think it's more fun to challenge yourself by taking a more complex piece and seeing if you can make it work with simpler rules, but that's just me! I'm not sure what I'm going to do yet, but I might take a SNES song and remake it in FamiTracker as if it were released on NES instead.
Let me know if you have any other questions or want to talk about arrangement techniques!
So i did this quickly cause i couldn't find sleep: https://www.wetransfer.com/downloads/dc26050135807be68a9b39f60b2172b120160310033038/459fe6abd1acd2c226e2c37347d569a320160310033038/d7cdda
As you can hear there are some clippings, probably due to a saturation when you were recording. And some of the trombone parts are a bit out of tune to me.
I still think it does sounds a bit better, i've raised the backing track volume, add reverb and EQ.
Let me know what you think