Yamaha GEW hardware

[iwillbeacircuitbender]

So what is with the numbering system?
Is GEW6 more primitive than GEW7 or higher?
Cause the Yamaha PSR-170 has version 12 of the AWM tone generation system, which is much better than the PSR-310,which has version 8
But the PSR E& and S series just have SWL, SWX,and SWP CPU's