The Zen universe of Roland Expained –

Roland has gradually put in place everything to lead to this moment: The ZEN universe of Roland. Roland is not calling this way. I do. in the 2010’s, Roland invented the ACB (Analog Circuit Behavior) algorithm to recreate in precise details the ways the circuits of a analog Roland classic synth and drum machine reacts. As a reminder, the ACB is found in the Roland Boutique series and in the Plugout synths (System8, System1, System 1m). The Plugout concept is really cool: you can have a VST plugin using ACB in you computer and send the exact same ACB plugin into you compatible synth, hence Plug-out. Then is runs on a dedicated machine! That already is a cool computer / hardware integration. But now, they go further. 

Roland came out with ABM (Analog Behavior Modeling) that runs Zen-Core hardware and Zenology software. This algorithm does it emulation in a different way. It look at how you play and tweak the instrument and will emulate the global result of the circuit. Where ACB would even calculate circuits not being used in the sound the ABM optimize the code to get a great sound with lest CPU. One of the main focus here is bringing quality sounds to an ever intertwined system of hardware and software.

Get more info about the differences between ACB and ABM.