it should be noted that the stereo sub setup will produce best results with acoustic recordings only, as there is almost never a microphone involved in electric bass (or any electronic instrument) recording. DI is used, and that signal is normally 'placed' equally in the l&r mains (not accounting for the 6th, or point one channel in sacd/dvd-a).

lexicon's dr. 'G' (with bass enhance) is taking a page from bob carver's holograph generator and requires PRECISE placement of both speakers and listener's ears. these 2 points are, no doubt, why bass enhance is said to be room and source dependent.

lexicon is the only pre-pro available with stereo sub outputs AND A SEPARATE LFE output.
my guess is that this configuration allows for the bass enhance feature, and is the only reason for it. otherwise, lexicon would be touting the many benefits of this configuration. the simple fact that bass enhance won't work if the LFE signal is summed with the redirected bass signal tells you that soundhound's setup won't either when there is LFE content.

80 hz is too high for a subwoofer.
1 subwoofer to reintegrate redirected bass into the soundfield is enough when the LP point is around 40-60hz.
the second subwoofer is needed for a discrete LFE signal, as the summing of LFE with redirected bass is where almost all bad things happen (intermod distortion, too much demand placed on a single sub system, crossover holes/humps, loss of any chance at stereo bass, phase problems, etc).
stereo subs, placed as soundhound suggests is a plus, but only for acoustic, 2 channel recordings and only if LFE ain't summed into them. also, the fact that 40hz is a wave that's 28 feet long, and therefore is reflecting off many surfaces before it ever gets out of the speaker, matters (this is, in fact, why bass is omnidirectional). soundhound has matched, ear level, direct radiating subs, so he hears the note first and the reflected notes afterward. most HT subs are downfiring or direct radiating, but sitting low to the floor and in the corner to use the corner for gain, which greatly lessens the stereo effect, especially at 40 hz.

dr. 'G' spent too much time developing bass enhance and overlooked the fact that the key to correct multi-channel audio bass is a DISCRETE LFE SYSTEM. among many other benefits of a discrete LFE system, it allows for a full range .1 channel by simply high passing a satellite speaker off the LFE sub (in dvd-a/sacd).

bottom line...i agree with soundhound, as far as placement of the subwoofers. i know the end result is real, and not perceived or imagined. when i record bass tracks in the studio, i have to play alone, while a monitor plays the song because headphones cause the music to arrive instantly to my ears and that tiny discrepancy in time arrival throws my timing off completely (as i am used to live performance much more so than studio work. i agree with lexicon as far as a discrete LFE output. i agree with stereo subs, but don't think they are the important part of the setup, unless 2-channel acoustic recording playback is your primary interest, and you have the room to properly place 3 subwoofers.

of the 3 things, discrete lfe output (and subsequently, crossover, phase and delay processing of same) is the most important, because, only then can you properly set up any sort of subwoofer system for redirected bass.