FYI the S900 conversion was fixed in the HxC software some weeks ago and converted S900 images to HFE with the SD HxC Floppy Emulator is working fine on the Oberheim DPX-1.
Reference (2020-05-26) :
https://sourceforge.net/p/hxcfloppyemu/code/2085/
Beta software having this fix :
https://hxc2001.com/download/floppy_dri ... t_beta.zip
EDIT : Another important thing to note about the S900 images support on the DPX-1 :
From the HxC2001 Facebook group :
Pl Haas wrote: ok i have figured out how it works. In order for you load a s900 image into the DPX - you need to use an image from the S900 where a sample is assigned to a S900 program. If you make a S900 disk image with samples only, it will create DE (Disk Error) message in the DPX. If you create an image with a program file and sample(s) but the samples are not assigned to the program, the image will load but the DPX will not respond to midi. Here is a S900 disk image with 3 samples, assigned to Midi channels1,2 and 3 https://we.tl/t-75OghEaDQl Many thanks once again for helping to get this working!!