linux - Is it possible to recover / convert / mount fakeraid image files? (TL;DR - have fakeraid images, want to convert them to mdadm images)

My Promise NAS NS4300N recently died (PSU or motherboard failure, probably the former as it has trouble spinning up the disks).

I've managed to dd(1) the drives (4 500GB drives in a RAID5 configuration) as images on a new server, even though one of the drives had a couple of read errors (conv=noerror ftw...).

However, as the Promise NAS doesn't use mdadm(8) for RAID but instead uses "hardware" RAID (aka FakeRAID), the resulting images look like this:

$ fdisk -l /local/media/promise.dd.1
Disk /local/media/promise.dd.1: 465.8 GiB, 500106174464 bytes, 976769872 sectors 
Units: sectors of 1 * 512 = 512 bytes 
Sector size (logical/physical): 512 bytes / 512 bytes 
I/O size (minimum/optimal): 512 bytes / 512 bytes 
Disklabel type: dos 
Disk identifier: 0xb95a0900

Device                      Boot Start        End    Sectors  Size Id Type 
/local/media/promise.dd.1p1         63 2929918634 2929918572  1.4T 83 Linux

$ fdisk -l /local/media/promise.dd.2 
Disk /local/media/promise.dd.2: 465.8 GiB, 500107862016 bytes, 976773168 sectors 
Units: sectors of 1 * 512 = 512 bytes 
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes

$ fdisk -l /local/media/promise.dd.3 
Disk /local/media/promise.dd.3: 465.8 GiB, 500107862016 bytes, 976773168 sectors 
Units: sectors of 1 * 512 = 512 bytes 
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes

$ fdisk -l /local/media/promise.dd.4 
Disk /local/media/promise.dd.4: 465.8 GiB, 500107862016 bytes, 976773168 sectors 
Units: sectors of 1 * 512 = 512 bytes 
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes 
Disklabel type: dos
Disk identifier: 0xb95a0900

Device                      Boot Start        End    Sectors  Size Id Type 
/local/media/promise.dd.4p1         63 2929918634 2929918572  1.4T 83 Linux

When mounted as loop(4) devices, the images look like this:

$ sudo lsblk -io NAME,FSTYPE,SIZE,MOUNTPOINT,LABEL 
NAME               FSTYPE                            SIZE    MOUNTPOINT     LABEL 
..     
loop0              promise_fasttrack_raid_member     465.8G
loop1              promise_fasttrack_raid_member     465.8G
loop2              promise_fasttrack_raid_member     465.8G
loop3              promise_fasttrack_raid_member     465.8G

Unsurprisingly, mdadm(8) is unable to read these, as it is unable to find a usable superblock:

$ sudo mdadm --verbose --examine /dev/loop0
/dev/loop0:
   MBR Magic : aa55
Partition[0] :   2929918572 sectors at           63 (type 83)
$ sudo mdadm --verbose --examine /dev/loop1
mdadm: No md superblock detected on /dev/loop1.

And of course:

$ sudo mdadm --verbose -A /dev/md127 --readonly --run /dev/loop1 /dev/loop2 /dev/loop3 /dev/loop4
mdadm: looking for devices for /dev/md127
mdadm: no recogniseable superblock on /dev/loop1
mdadm: /dev/loop1 has no superblock - assembly aborted

I thought I could try to read/examine these using dmraid(8), as this is advertised as a tool to "discover, configure and activate software (ATA)RAID". But as far as I can tell, this statement is only true if the drives are exposed through the BIOS, which these clearly are not, being that they are loop(4) devices:

$ sudo dmraid -ay
no raid disks

Do I have any chance at recovering the data via software? Or is my only option to find hardware that can read physical drives with the data on them (e.g. a Promise PCI card)?

Thanks for reading.