Heh ... Actually 720K/1.44 MB is pure HW issue in case of Atari ST serial. ST(E) does not handle HD floppies, TT and Falcon do. Saying HD (High density, actually is is quad density) is much better than 1.44 MB.
And in case of Atari SW is much more flexible than in case of DOS and especially Windows. You can handle 800KB, and even 880KB floppies with ST(E) - it is still DD (Double density).
In case of HD multiply it with 2 . I used 1.6MB HD floppies with my modded ST very well. Could go on 1.8, but that was not reliable, and was slower because need for interleave.
Now, SW is little longer story because need for proper step rate setting, but actually you can work with HD, so for instance 1.6 MB floppies very well even with TOS 1.00 - after doing HD floppy mod or upgrade in ST.
Now, if using some HW floppy emulator as Gotek - with unmodded ST(E) you can not use HD images unless SW in Gotek makes it possible since no physical limit on media - but that actually still works in DD mode, with lower transfer speeds, since original FDC supports only that. And some SW may not like it, because timing is not as is with real floppies.
I looked Gotek site, and what is there is just not looking good for Atari users:
"Compatibility: 3.5"- 720kB: 80 tracks /9 sector"
I'm sure that it can 10 sectors/track and probably 11 too, otherwise would be useless for Atari users.
But it seems that no model what can HD and DD - or it depends on firmware ?
Edited by ParanoidLittleMan, Sun Nov 19, 2017 4:36 AM.