Paul-
The speakers I heard were correctly set up per Gradient's instructions: toed in at a 45 degree angle.
Measurements by Helsinki 1.5 owners show the speaker rolls off below 50 Hz.
Even TAS reviewer R.E.Greene, who gave the speaker a TAS GEA says the speaker may need subs in some rooms.
You can go on Greene's forum and see measurements at:
http://groups.yahoo.com/group/regsaudioforum/
Have you taken any measurements? If so, please post them on Greene's forum.
PS- here's tip for you, check the tightness of the fasterners on the woofers and midrange drivers.
PPS- what are those black things you have under the speaker bases?