Bob, this past weekend, I assembled my 70 series Argosy desk for my DM24 and I originally wanted to install my MX2424 into the horizontal section of the desk but there are a couple of issues with this arrangement:
1) the support legs actually run from front to back in the base unit of the desk and will prevent the recorder from sliding all the way into the rack cavity. I can only get about 15" of usuable depth in the horizontal section - 5U of gear - because of that bar.
2) This same support leg measures around 6" or so from the outside edge of the base unit so if Argosy has a blank insert unit that were around 7" wide and one that were about 14" wide, I would have been able to offset the rack and drop the recorder into the horizontal section. This offsets the DM24 from center of the desk but only by a few inches. I have not checked into this with Argosy, yet.
The vertical rack section gets even less and the mounting angle prevents the recorder from even sliding all the way back, by about 4 inches. Even if you were to find a way to mount the recorder into this section, it is really meant for smaller, lighter gear - the rails they supply are held in place by (2) screws per side (7U of gear space).
I wanted you to know what my installation issues have been so you can make an informed decision regarding the placement of your recorder since the DA7 and DM24 argosy desks are virtually identical. Assuming you have sufficient space in your studio, you could go with a 90 series desk and that would probably solve the problem for you. For me, I ordered a Raxxess ERK 20 since I only use my MX2424 for transfers into my DAW from field recordings.
