Overview
SY99
RCM synthesis engine
SY99's synthesis engine is called RCM (Realtime Convolution and Modulation).
It combines PCM and FM synths.
Not just layering the two synth parts, SY99 can use PCM sounds to modulate FM part.
AWM2
The PCM synth part is called AWM2 (2nd Generation 16-bit Advanced Wave Memory).
It's a 16bit PCM synth with two multi-mode digital filters per oscillator.
It has 8MB ROM and 512KB sample RAM with battery-backup, which is expandable up to 3MB.
AFM
The FM part is called AFM (Advanced Frequency Modulation).
It's an advanced version of YAMAHA DX7's FM with the two multi-mode filters and more powerful modulation routing.
It has "Free Algorithm Edit" function when edited via SysEx.
Effects
SY99 uses YAMAHA SPX900's effect processors, and up to 4 effects can be used.
Drawbacks
Limited realtime control shared by most SY series, except TG300;
When Filter EG is used, Filter LFO and other realtime filter control are disabled.
There are too many parameters.
Thus, I made an editor that controls meaningful groups of parameters at once.
There have been many attempts to reduce the number of synth parameters,
as seen in Roland SoundCanvas.
Often, such attempts are only useful for fine-tuning and not for creating new sounds.
I tried the least set of parameters that makes editing intuitive and speedy enough,
but still makes it possible to create new sounds.
This is just one idea to organize SY99's vast parameters,
and there can be many other ways to create better UI.
Related SY/TG series
SY99 is the upper version of SY77/TG77, which shares RCM engine.
SY77/TG77 have 4MB ROM, no RAM and YAMAHA SPX90II effect processors.
SY55/TG55 are AWM2-only synthesizers without FM.
They have 2MB ROM, and the effect processor seems to be comparable with YAMAHA R100.
Rhythm Programmer RY30 / RM50
uses essentially the same synthesis engine as SY55/TG55 without effects.
SY85/TG500 are AWM2 synthesizers with 6/8MB ROM, SY99's effect processors and more polyphony.
They can accept SY99's RAM board, and SY85 has 512KB RAM pre-installed.
TG300 is an AWM2 synth with 6MB ROM and 2pole filter.
It uses SY99's effect DSP.
SY22/TG33/SY35 uses
DASS (Dual Architectural Synthesis System) engine with Dynamic Vector.
It can layer 12bit AWM and 2-operator FM, but there's no interactive modulation like RCM.
TG100 is the scaled-down version - AWM playbacker without FM and Vector.
Their AWM section has some samples that resembles SY77/99.
SY99's Preset 'Itopian'
Emulated with TG33
'Itopia' by TG100
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SY99
Deep Synthesis: Home
8. 12. 2003