They do not need to be updated. The SD2 (which I have) has certain patches in it and you can choose them once the pat file is loaded.

There is no other way to do it.

If you want to duplicate the work, you can make your own patch maps, but they are done and work well.

Patch maps are static, there may be new sounds to download from Ketron in Italy, but I doubt it very much.

If I choose an organ and then press the plus sign I get all the family of related patches..whatever is in that SD2 box.

I don't have an sd4 cannot comment.

John Conley
Musica est vita