Looking at H-B magnetic curves of iron

They are very linear especially at low H (magnetization) field values.


Does the same happen with old magnetic tape that had low coercivity and retentivity?


For example 3M Scotch 111 used to record Kind of Blue - Miles Davies?


Would a Quantegy 632 preform similarly too?


http://www.tapeheads.net/archive/index.php/t-56448.html