4 TB Sharespace Raid 1: can I get a single 2 TB volume mirrored instead of "two-mirror"?

[sharespaceuser]

disk 1 gets mirrored on disk 2 and disk 3 gets mirrored on disk 4 so i have 2 raid1 volumes

but i just want have one: disk1+2 together mirrored on disk3+4

is that possible?

[sharespaceuser]

ok i got an info from wd support, that this is not possible