Complex sentence: Casio's older CZ synthesizers suffered from a lack of modulation as they only contained one LFO used only for oscillator pitch, the FZ-1 greatly improves on this by allowing the single LFO to control oscillator pitch, amp level and filter level.
Split into simpler sentences: Casio's older CZ synthesizers suffered from a lack of modulation as they only contained one LFO, used for oscillator pitch. The FZ-1 greatly improved on this by allowing the single LFO to control oscillator pitch, amp level and filter level.