For anyone interested, I found this
report on group delay. It's fairly complicated and admittedly lost me at certain points, but what I read in the report seems to confirm that the difference between a good vented sub and a good sealed sub aren't likely to be large cause for concern.
In this test, the difference of max delay between their vented and sealed sub was around 2 hundredths of a second.
If anyone is up for more Q&A (a dangerous proposition I've seen), I'd be interested in a brief explanation of what the author means when he says that one system is a "second order system" and another is "a fifth order system." I've heard those terms before but do not understand the distinction.
Jason
