Well, think of it this way:
The HxC has a three big things to consider as far as configurations go that are machine specific. Meaning an Atari ST and a Yamaha TX16W, for example, cannot be configured the same way as they are different machines.
1) The pinout of the floppy drive interface. Meaning that most older machines will use the older Shugart standard (or a modified version of it) where there is a ready signal present. A lot of newer (at least in terms of floppy technology, ha ha) machines use the PC standard where there is no ready signal available.
2) The format of the disk. Not only do disks differ in their unformatted types (5 1/4" single-sided, 5 1/4" double-sided, 3 1/2" single-sided, 3 1/2" double-sided, 3 1/2" high-density, etc.) but also each disk type can be formatted with a different layout. As a common example, 3 1/2" double-sided disks are usually called 720K because that's how much they hold when formatted under DOS whereas they also tend to hold 800K when formatted under other machines like the E-mu Emax, etc.
3) DS0 versus DS1. The first or only drive in a PC (drive A:) is forced to DS1 whereas most other devices will expect DS0. While DS0 is a very common setting for devices using HxC (as a lot of them are Shugart derived), I highly suspect the ASR-X expects DS1.
So, you not only need to tell the HxC what drive signals to expect (PC versus Shugart or some variant thereof) but also the disk format layout (720K, 800K, 1.44MB, etc.) Once you figure out what the Ensoniq ASR-X is expecting for both then you should be well on your way to finding or creating the appropriate configuration file and HFE settings.
I could be mistaken, but like I said before, I think the ASR-X was the odd-man-out when it comes to Ensoniq devices because I don't think it used ASR10/TS10/TS12 type disks or drives. I believe it is all PC standard, so... 1.44 MB disk, PC interface (no ready signal), and drive forced to DS1.
If you have a spare 3.5" floppy drive taken from some random PC then toss it into the ASR-X. If it works just like the original floppy drive did then that will tell you exactly what you need to know -- the ASR-X uses the PC standard. And if that's true, then you know everything you need to know about how to configure the HxC.