I've only heard of additive referring to synthesis through summing series of sine waves. Ring mod and hard sync are pretty common in subtractive synths (my Mini

I've only heard of additive referring to synthesis through summing series of sine waves. Ring mod and hard sync are pretty common in subtractive synths (my Minilogue has both for example). Additive would generate sounds without any sort of time series "filter", and would attenuate the sine series before generating them.