You could control a bunch of functions on the 4K with Lemur. And have the screens update with real time visual feedback with bi directional MIDI. But would need to make a template. You could use the much cheaper TouchOSC or MIDI Designer Free or Pro. But Lemur is the only one I can can confirm has full Sysex support to be able to externally control all the functions on the 4k that respond to external controllers.
And yeah man no doubt, if BM2 just had soundfont or .sfz multi sample solution, it would literally do everything a 4k does with a minimum of 1GB RAM looking at recent iPads. At times I use BM2 like a touch screen Recycle and just save to folders. Not bad considering even at full price it cost 1/10th of Recycle's price, and that's just one element of BM2.
I was really pleased when they added the quick load sidebar toggle for getting sounds on pads.
Meanwhile iMaschine is still lo res and too limited and iMPC assumes I would not need folders for my samples.
There's a thread here where a user is already working on a nice JJ-XL template for Lemur. I haven't started mine for either JJ or the 4k. Lemur is so deep it is going to require studying the list of functions I can map, then determine how many pages of controllers I want, and really draw it out on pen and pad first.
tsutek, is already really rolling on his Lemur Template.
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