Oh hell, Craig, just put a camcorder in front of your test equipment and go on vacation while it records the data...
I just found out that how it actually sounds doesn't matter.
In fact, if it can't hit 121 dB 'cleanly' at 20 Hz, we can all just cross it off the list, so do that test first...it may save you some time.
And, while we're on the subject, you haven't sat your wife down and explained why it doesn't matter what the sub looks like??!!
Dave