I just bought MODX8 (a Xmas gift to myself) and unpacked it yesterday. I am a total newbie to the world of synthesizer. With few experience with guitar and piano, I had some audio knowledge but the memory and my understanding is very vague.
I googled on the Internet and try to learn about the ABC of synthesizer, and I found this simple ebook: researchgate.net/publication/317746236_Synthesizers_A_Brief_Introduction, which you can find it offered free to download on ResearchGate.
Thanks for a lot of great posts, especially the post "MODX Essential Knowledge Guide" posted by Derek . I follow that document to navigate MODX8 pretty well.
Covers the Yamaha MODX6, MODX7 and MODX8