Yamaha SY99, Owner'S Manual

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About the SY99: RCM hybrid synthesis
The SY99's RCM hybrid tone generation system fuses the realism of digital samples with the expressive
power of FM. It uses Advanced Wave Memory 2 (AWM2) and Advanced Frequency Modulation (AFM) in
conjunction with digital filters to allow a wide variety of sound creation techniques.
Advanced Wave Memory
2 (AWM2) AWM2 uses 16 bit linear sample reproduction with proprietary Yamaha con-
volution technology (digital filtering) that allows you to emphasize or cut any
desired portion of the frequency spectrum with full realtime control.
In addition to advancing beyond the FM synthesis capabilities of the DX7 and
previous Yamaha synthesizers, AFM allows you to filter and envelope any
AWM waveform and use the shaped waveform as part of an FM algorithm to
apply frequency modulation, creating partials that were not present in the origi-
nal AWM waveform. This modulated waveform can be processed by additional
digital filtering.
One of the greatest advantages of RCM hybrid tone generation is that it fuses
the realism of digital sampling with the expressive power of FM. Keyboard
dynamics and controllers can be used to control nearly any aspect of the sound,
allowing great musical expresiveness.
The SY99 allows a wide variety of synthesis techniques to be used, and digital
filtering is always provided for each AFM or AWM element. The following dia-
grams show how the RCM hybrid synthesis system can simulate many of the
analog and digital synthesizers of the past.
Advanced Frequency
Modulation (AFM)
Dynamic touch and control
The possibilities of RCM
hybrid synthesis
Filter style "analog" synthesis: Single cycle AWM waveforms can be
enveloped and filtered to simulate analog synthesizers. (Various sawtooth
and pulse waves are provided, and the SY99's filters can be configured as
24dB/octave filters with resonance adjustable into oscillation.)
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