My first "real" synthesizer, so it will always have a special place in my heart.  I bought this used in a small Rome music store in 1987.

I upgraded to the wonderful world of "P.D." (Phase Distortion) synthesis from my trusty Gem DSK-8, which my aunt bought for me (thank you, aunt!) on 5/22/1986 (still remember the day!), because even though the DSK-8 was capable of "realistic", that is- pcm sounds, and even some mean weird sounds, I had occasion to play a Korg Poly-800 that belonged to a school mate, and fell in love with it.

A "real" synthesizer sounded so warm, full, interesting, and "polished", as opposed to the "plastic-sounding" home keyboard I was used to.

I spent many nights programming new sounds with it!  I still have a notebook full of hand-written patches.  I was totally in love with the CZ-1000, and literally fell asleep programming patches and recording the outcomes on my VestaFire 4-track cassette recorder!

I higly recommend reading the CZ-1000 (or CZ-101, it's the same) manual if you are starting in the world of synthesizers!!!  There are two books, and in the first there is an excellent explanation of how synthesis works, hands on examples, etc... it is how I learned!

The CZ series came after the mythical Yamaha DX7, so Phase Distortion sounds similar to FM, but does have a character of its own.

Don't forget to check out the "Internal" presets!  They are beautiful!  To recall them, turn your unit upside down, and press the reset button with a toothpick or similar object:  Ta-da, the Internal sounds are back.

The CZ is capable of a myriad of interesting sounds, the Factory and Internal sounds are only scratching the surface of what the PD synthesis can do...

I also have a couple of CZ patch books around, I have to find them...