There have been previous discussions on increasing rotor diameter so that magnets are moving faster over the coils,and it it has been agreed that there is no advantage in this,providing all other things remain equal( same no of mags and coils etc). SO! what would be the effect if I had,say, 24 magnets,and instead of building a dual rotor alt with 12 mags on each, and 9 coils, I built a larger diameter, single rotor machine with 24 mags and 18 coils( with core behind). I would have doubled the number of poles and coils, and increased the speed of mags over coils,but probably have the same amount of flux, or less??. As there is nothing new under the sun, this probably has already been tried, and you guys will have the answers. Opinions please.