NEW ITEM! Had I not heard it myself at the 2013 Rocky Mountain Audio Fest (Denver, CO)- I wouldn't have believed it: A demo with a Bose Wave Radio and the FEQ + HFT setup changed that. Synergistic claims this has an effect on resonances and frequencies above the audible band, and goes on to explain some of the principles of operation. Must be heard to be believed.
This system has two parts: 1) The FEQ which generates a high frequency signal (above audible threshold) and 2) The HFT's- which interact with the FEQ to complete the system. The HFT's may be used independently of the FEQ, as a standalone solution.
Read more about the HFT and FEQ room tuning tweaks at the links below: