This machine surprised me totally with it's very unique sound, and it's CV -controlling features; you can send sound in and out in a great variety of ways, connect it to many other synths, and waveforms can be changed in a nice flow - this synth gets me euphoric! And I must say that I'm not a beginner, and I do NOT recommend this synth to beginners. Why? For example at first there was something unique in it in a mysterious way, so that for a week or so when it arrived I couldn't somehow get a sound out of it! But when I finally realized how unique it is, and started to learn it's abilities, (because every synth is unique), the power-full sound was so "phat" and 'analogue' that I was in a state of awe before it! I was trying it in my mother's house, and she screamed when I finally started to play it! Also you can connect a MIDI keyboard to it too, but I have now concentrated in other things with it. For example right now it is connected to Behringer Crave, Korg Minilogue XD, Arturia Minibrute 2 and to an old and working Yamaha CS-5 (which have been customized/tuned/pimped so that is now has CV -abilities! Also, I have used Roland's small but great P-6 -sampler to push sounds through Kobol's AUDIO IN! So, what I'm saying is that Behringer's Kobol Expander is an unique machine, which can be used it many different ways, it is truly extremely versatile! Jimi Hendrix used to sleep with his guitar, and Kobol is a synth that make me want to do the same! :D Also I read a bit about the original Kobol's history, and there where few Kobols made in France in the 70's (about 300 machines, I think?), and although I can't prove it, I think that Daevid Allens band Gong used it! Kobol in itself, even when not connected to multiple other machines, has a beautiful and recognizable 'voice', and I think I hear that fore example in Gong's 'Live In Bataclan' -bootleg.
So: to me, it is a truly unique, but I would not recommend it to beginners. It is very versatil build like a tank, the knobs are very sensitive to touch. Connecting it to other machines through CV (although it has MIDI too etc.) is one way to use it, but you can push sounds from Minilogue XD through it or many ther ways you can find out with it; playing with is an adventure! I truly recommend it to freaks like me, and also it can be connected to Eurorack systems too if you wish, it comes with cable to connect it. But I just use it in my own shamanic way, and I must say it could be called a 'psychedelic synthesizer'! Peace out! (((((*)))))
