I would not say I did it with any great accuracy… and I did make the presumption that the drivers were the model they were labeled and used the driver manufacturer’s TS parameters.
The graphs that it created looked like what I was hearing, esp when increasing the input power…
So not any degree of accuratey at all but it explained what I was hearing and the difference between a cab that sounded fine at low practice levels and caused massive issues for the live sound engineer turned up.
from memory the box was too big for the drivers and the port (a hole cut in the baffle, so 15/18mm deep) wasn’t tuned quite right- so with a slight increase in power the bottom end dropped of and there was a massive spike in the mids that cut through thr mix in a slightly uncontrollable way.
since then I have had or used: ACME, Barefaced, Mesa Boogie, Gallien Krueger, Ashdown and now BCcab and Stevies LFSys and am happy that the designers of those cabs had and used the TS perameters to create a lovely set of bass cabs.