On Sat, 2 Jul 2016, Peter Coghlan wrote:
  The original ADFS had 16 sectors of 256 bytes per
track. However, it appears
 that more recent ADFS formats use 5 sectors of 1024 bytes.  There are more
 details here:
 
http://mdfs.net/Docs/Comp/Disk/Format/Formats 
Thank you!
Note: the use of the term "quad" density in this chart is not the same as,
but a more rational use of the term than, the misuse that was prevalent in
the days of 640K - 800K 5.25" CP/M