I figured out REW over the weekend, and here are 2 graphs I made with my 88.5liter vented shiva tuned to 25hz.
First, near field. The SPL was calibrated around 85:
first sweep shiva.jpg
Next is taken around 8 feet away, as close as the wires would allow to listening position. SPL at the proper 75db as I figured out what I was doing. There are 2 sweeps here to see if the outcome was repeatable:
far measurement shiva.jpg
Any advice on these? I am building a new sub to replace this one and will measure it in the same spot when completed.