Jason,

You can see my measurements (using REW) as posted on page 1 of this thread. It's a link to the Home Theater Shack, where I posted a number of plots of the 990's frequency response for the various modes.

I think the response that Scott gave is with respect to someone's (Kris, I think) assertion that since there is some time delay from input to output, then there must be some A/D/A conversion going on. It's slightly different than the bypass bass management problem that is the focus of this thread.

As you will be able to see from my original plots, there is indeed some type of high-pass filtering going on, but it's constant with respect to the varying crossover settings. It starts at about 100 Hz, IIRC. Also, although there is some type of strange filtering going on, we can't assume that it's a digital filter (nor can we assume it's not). It's just a filter at this point.