In a perfect world your room dimensions would be 14.5 X 23.5 X 9'. That gets you the Golden Ratio in all 3 dimensions, and a good starting point. Unless you use the Bolt method, in which case it's off the chart. Go figure. Literally. You still need to calculate and deal with the eigenmodes in those 3 dimensions plus axial, tangential, and oblique. Like this:
https://amcoustics.com/tools/amroc
https://amcoustics.com/tools/amroc