I can see how Audessey may help smooth FR in the upper frequencies but there is no way it can calculate optimal settings down low. The physics involved make it very difficult for an automated program with limited processing power to do well. Fixing FR problems with automatic electronic correction is a tricky proposition requiring huge amounts of dedicated processing power to calcualte iterations.
I have rarely seen any automated program which actually set equalization/delay/crossovers correctly for subwoofers. Its actually refreshing to buy equalizers (DEQ2496) with auto-programs where the manufactuer(Behringer) specifically warns not to use such programs for frequencies less than 100hz.
The fact that the Audessey programs in receivers are marketed as one stop silver bullets is disingeneous to me. To do the job properly across all frequencies requires far more processing power than you find in the typical receiver. Indeed even to address correction strictly in the lower frequencies is a formidable task. The Velodyne SMS-1 for example does a reasonable job up to 200hz but limits resolution to 1/3 octave because of processing limitations. Meridian and Lexicon limit their scope to only addressing long decay times rather than flat FR below 250Hz. Interestingly both of these companies recommend using room treatments to address flat FR rather than use equalization because of the limitations in the devices.
One always gets better results by doing such equalization and delay settings manually.
