FM synthesis is additive, and it's a fair point you can play .wav files directly on your machine. I have been tying them to external events which was a bit more difficult.
Additive may not mean what you think it means perhaps? FM involves modulating the frequency of one oscillator with the value of another, whereas additive synthesis involves simply (lol) mixing multiple sinewave oscillators to generate a harmonic series.
Unless there is some more fundamental way in which they are equivalent, in which case I would be eager to learn more.
So I stand somewhat corrected, I had a memory of Chowning describing it as additive in his book "FM Theory & Applications" which I got with my TX11 but as it turns out he felt calling it additive was too simplistic as modulating a frequency is multiplicative. Each 'Op' however is added together to give the resulting tone. Now contrast that to my Arrick where I'll feed a square wave into a VCLF and peel the push filter out the harmonics over time to get a nice 'gong' sound which is definitely subtractive.
I did get a chance though to re-read chapter Chapter 3 "What is FM" and marvel at the relatively simple way it composes into very complex waveforms.
It's possible to calculate the exact frequencies that would be generated by FM synthesis and additively produce exactly those partials that are under Nyquist instead. IIRC, "alias-free" FM synthesis is the name of this technique when used to produce cleaner, band-limited waveforms.
Actually the DX/TX series allowed limited additive synthesis using their 4 or 6 operators (oscillators in Yamaha lingo). That's how the phonic-wheel organ sounds were programmed.
