Grumpy_Mike:
For this project I think you need some way of displaying the current settings of your patch so you get feedback as to where the parameters are.If you use pots then you could arrange the code that it only changes the midi parameters when you actually change the pot, not when you change the patch.
You have to read the encoders at about 1mS intervals so as not to miss anything. A rate of 200mS is way too slow.
Sorry for the confusion, I was assuming turning the encoder half way takes 200ms. Not that scanning them takes that long. As I said, scanning would need to happen at 4ms at most. Assuming I turn two encoders half way within 200ms means 200ms/48 inputs = roughly 4ms per input.
Also visual feedback for the parameters isn't absolutely necessary. If I were to use potentiometers I could neither address several synths at once nor store patches because values would always have to be absolute, and that's just not practical I'm afraid.