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An underrated synth although it does lack the Virtual Acoustic (VL) Synthesis of the EX5. It did have FDSP (Formulated Digital Sound Processing) Synthesis which I don't believe I have ever explored.
Details:
"The EX7 features a unique Extended Synthesis system which incorporates a number of the most advanced tone generator technologies currently available...plus a full-featured sampling system. It offers a Four-Element Voice structure which allows for up to four independent waves from any of the tone generators. The tone generators implemented here include AWM (Advanced Wave Memory) Synthesis, AN (Analog Physical Modeling) Synthesis and FDSP (Formulated Digital Sound Processing) Synthesis. According to Yamaha:
"AWM is Yamaha's original system for effectively using sampled waveforms in synthesizers and tone generators. The strength of AWM synthesis lies not only in its extraordinary ability to "shape" and control the sound of the samples with a comprehensive system of envelope generators, filters, key scaling parameters, modulation, and more. AWM voices can have from 1 to 4 AWM elements. Each AWM element can use a preset wave or a sampled waveform. The ability to combine AWM elements means that you can, for example, combine separate samples for the attack and sustain portions of an instrument's sound, with independent control over each.
Yamaha AN Synthesis (Analog Physical Modeling) offers all the benefits of traditional analog synthesis with the stability, reproducability, and precise control of digital technology. It is capable of accurately reproducing the sound of classic analog synthesizers without patch cables, setting charts, or the frustrating instability that was the bane of the analog age. A standard (Poly) AN voice can have 1 AN element and from 1 to 3 AWM elements. Classic analog synth type sounds can be created with the single AN element alone. AWM elements can be added as necessary to 'modernize' the sound.