There are 3 upgrades:
MDx - $1250 - provides for native DSD256 with USB, and greatly improved Master Clock Sync.
M1 Series 2 - $2500 - replaces most of the chassis parts to larger ones to house and the larger power supplies that are both found in the M12/21 products.
SE upgrade - $1000 – adds stillpoints, hard wiring, fuses removed, and resetable fuse added.

