Thank you Phil!
The link for the article about nearfield sub placement is from hometheatersound.com and this position is often recommended by Dr. Hsu:http://www.hometheatersound.com/feat...n_20060801.htm
I ran through quite a few DVD scenes and music CDs today with the VTF-3 MK3 corner loaded, and while it was indeed powerful in that location it was setting off too many resonances and rattles in the nearby walls, fireplace, and windows. I used it both with Turbo (max extension mode) and without (max output mode) and I continue to prefer the max output/no turbo mode in my room because of superior dynamics, increased fullness and slam in the mid-bass, and less localization of the sub location.
Next I tried placement on a sidewall to my left and the sound there was really good, with less room resonances than the corner had. But I've been talking with my very nice neighbors about the fact that I have on occasion rattled the living room walls of their own house and today they heard some rumbling from my testing, so in an effort to avoid bothering them I once again tried that nearfield position with the 3MK3 side-firing right into the left side of the couch 3 feet from my listening seat (ports firing towards the front of the room). The benefits here are numerous as the sub is moved further away from my neighbors wall, it functions nicely as an end table with a lamp placed on it, and best of all the impact - WOW!!! My jaw literally dropped as I listened to the storm and subsequent plane crash near the beginning of Flight Of The Phoenix - each wave of LFE plummeted my listening couch and was strongly felt in my entire body, and I was picking up more subtleties of tone and texture in various bass effects compared to having the sub placed further away. When the plane takes a roll before the crash there is an extremely strong 30hz sustained tone and when it hit it was like getting an intense full-body massage!
The Star Wars I pod race, Finding Nemo submarine and Darla tapping scenes, JPIII dino fight, and WOTW pods emerging were all handled with great authority and an almost frightening palpability transferred through the couch to me. With nearfield I get less wall-shaking in the room but much more impact and vibration directly on me at the listening position, whereas placement close to room boundaries shakes all the walls in the living room but with less visceral impact on me. In nearfield I continued to prefer the sound of the 3MK3 without Turbo in the extended output mode, both with movies and music, as the additional headroom and full mid-bass impact are so addicting to me (kick drums in ext. output mode are clean, tight, and punchy). I'm sure the sub is not reproducing much below 20hz with this mode and placement, but I do not miss the mostly inaudible stuff in the teens because what I'm getting from 20hz on up is so awesome.
I still believe SVS makes excellent products as well, but it is clear to my ears that this VTF-3 MK3 is truly something special, certainly more accurate and musical than my SVS and a true bargain at $649 intro. And what has really surprised me is the power and dynamics in extended output mode considering my large open space (close to 7000 cu. ft. total and a stairwell opening). This is as much sub as I can use in my current house without driving my neighbors insane and I am delighted with the way it blends so well with my Ascend speakers (crossed over at 80hz/front and 100hz/surrounds I cannot localize it at all with nearfield placement). It's a keeper!