Jack, I find doing these side by side comparisons a lot of fun (and work) and always come away learning what the subs or speakers are capable of. Given how quickly we humans adapt to our environments it can take a long time to key in on a single subs sonic qualities compared to the side by side testing. I still have some more testing and listening to do with the 400.

St. Pat, you'd have to hear for yourself just what a awesome difference stereo 400s make to soundstage and imaging. I have now tried them with 3 different sets of speakers and I was wowed by the 400s with all three sets. The fact they are so small makes setting them up for 2 channel listening a relative breeze. While they are being proposed primarily as a multi-sub HT solution, I'm just so impressed how they perform in stereo.

Over the next few days I'm going to test the 600 and 400 pair in various locations to see how effectively they tame the nodes. I'll take shots of the SMS display for comparison.

John