FM concepts from the DX7 apply to all six-operator and four-operator Yamaha FM synthesizers

The FM synthesis concepts and voice architecture (operators, algorithms, EG, ratio, output level, velocity sensitivity, LFO) are consistent across the entire Yamaha FM family: DX7, DX7 II-FD, TX7, TX802, SY77, and the four-operator TX81Z and V50. Patches built on two-operator techniques generalize to four- and six-operator instruments because the core principle — carrier frequency-modulated by modulator amplitude — is unchanged. The main differences are sound storage (disk drive on DX7 II-FD, RAM cartridge on original DX7) and the availability of function data stored per-patch. Beginners can learn on any of these instruments and transfer the understanding.

Examples

FM Demo 1-A uses only Op. 1 and Op. 2. This two-operator technique can be recreated on the four-operator TX81Z, which has enough operators to run the same carrier-modulator pair.

Assessment

Name two four-operator Yamaha FM synthesizers that can replicate the two-operator FM techniques from this book, and explain what architectural property makes cross-synthesizer transfer possible.