While there's no doubt many find FM synthesis hard, I disagree that the interface didn't make it way harder than it needs to be. I am absolutely in love with t

While there's no doubt many find FM synthesis hard, I disagree that the interface didn't make it way harder than it needs to be. I am absolutely in love with the Yamaha Reface DX that I have, and greatly enjoy editing and the real-time controls over the parameters that it offers with its mere 4 touch sliders. I think the direct control boxes didn't sell well because not enough keyboardists grokked FM well enough to mess with the sound live (and didn't expect to learn) -- and also because nobody loves add-on boxes. A better UI, I think would change things. Again, that's a lot of what makes the Reface DX fun. In any case, perhaps the DX is not the best example here. A better example would be the many 90-s and early 2000-s synths, which were all about menus and you couldn't do anything immediately. (Microkorg would also fall into that category, its knobs are deceptive: what each knob does depends on the value of two or so others knobs. It's menus but without screens. And it's a VA synth - no reason it couldn't be more like Roland Gaia which is one-knob-per-parameter).