Here's a handy tip to determine if a given-sized server rack is sufficient for all your audio kit.
This planning is preferable to buying an incorrectly sized rack.
For example, if it's for a planned 16u rack, open/create a 16-row spreadsheet.
Each cell in the first column represents 1u.
Merge cells for 2u, 3u component/ventilation/blanking panels.
Name each merged/cell with the component name.
Overall, this represents the front-mounted contents of the server rack.
In the second column, repeat the above, but identifying hidden/mounted rear components - such as an AppleTV, network hub, a power distribution unit, or active cooling units, for example.
In advance, this avoids any unintended interference between front and rear-mounted components.
Such advanced planning minimises time spent on any potential frustration/problems of repeatedly mounting/removing/mounting each and every component until you get it all to comfortably fit.