I suspect ‘double magnet’ refers to a driver with a magnetic flux twice what a standard driver has. This Chinglish marketing speak usually is referring to a high (~1.0+) Tesla magnet driver. A Tesla driver can, in theory, be a good thing (assuming) the rest of the driver is designed properly. Think of it like very sticky high performance tires on a car. It’s great if they come from the manufactures on an Italian sports car, because the rest of the car has been built to take advantage of the tires. But those same tires would be a total waste on a Toyota mini-van. The end result of Tesla magnets will vary, depending on the rest of the driver’s design (diaphragm, tuning, impedance, vents, etc). There’s not one singular summary, like “a Tesla magnet always = this”. But in general, the stronger driver magnet usually translates to bass having a deeper extension, faster speed, and tighter sound. But again, the overall tuning can totally change that. Some gear that uses high Tesla drivers are ibasso IT01, beyerdynamic T1, beyerdynamic Xelento, Fostex TH-X00, ZhiYin Z5000, and others. Personally, I think the ZSN was pretty good just as it was. So I’m not sure why KZ felt the need to immediately follow up the very recent ZSN with a 2nd revised version. KZ usually has an 18-month cycle on model upgrades. The ZSN literally just came out a few months ago, and had a very positive reception. We’ll just have to wait and see what exactly ‘Pro’ means. Just because the word ‘Pro’ is after something doesn’t mean it’s better (although it does almost always mean a higher price).