I found the following review for the Hallograph Soundfield Optimizer.
While I am not an acoustics expert, it seems to me that this is one of
those products that are best appreciated while wearing a tinfoil hat.
Any other opinions?
http://www.shakti-innovations.com/hallograph.htm
"I purchased a pair of Hallographs within 10 seconds of putting them in
a position about one foot to the outside and two feet to the rear of
each of my Legacy Focus Speakers. These are fantastic room defect
correction devices, truly sound field optimizers.
My room is 25' X 21' with the speakers six feet in front of the rear
long walls and six feet apart. I have 2.5 walls lined with built-in wood
LP storage cases for 12,000 LPs and 5,000 78s, two pair of stacked metal
CD storage drawers (4500), two 4X4 side wood casement multi-pane glass
windows and a 3.8" X 8' rear window (same type), rear 5' X 8' equipment
closet (open) and 8' to 12' vaulted ceiling. The walls are 8" to 12"
thick with dual 5/8" drywall, 5" steel rebar reinforced slab floors and
drywall ceiling (not good-highly reverberant). This room has a slap echo
and over reinforces bass frequencies. There are lots of objects in the
room.
I have Grover electronics and ICs, moderately high end front end
equipment. The sound has always been bass heavy, slightly boomy
(dependent on music), always located between the speakers or at the
speaker.
The Hallographs immediately tightened the bass, providing a focused
sound, ameliorating the boom and providing a punch instead. The bass
harmonics opened up. The highs are more open and the mids have at least
twice the resolution. Upon further adjustment by 1/8" to 1/4" swivel on
the top, I was able to lock in the amount of openness (side to side
width) and fullness (depth). Recordings vary so that occasionally I'll
tweak the swivel 1/4" for more openness or more depth.
I also tried a second pair placed at mid-room with the array facing the
speakers. This was too much (as in too much fun)! The speaker sound
truly overcame the room artifacts and delivered a you are there
experience. Placing the second pair along the rear wall (listening area)
did not provide much improvement. I am hoping to purchase the second
pair. I previously used four Room Tunes. They aren't worth much now (to
me) since I installed the Hallographs.
The Hallographs are equivalent of doubling or tripling the speaker
quality, or of installing Grover ICs (well, not quite that much of an
improvement, his ICs are spectacular). Try them for free and see if you
can give them back after 5 or 10 seconds of listening. They are that
good. They are also slight in appearance and don't require me to alter
my room contents, design or place large, cumbersome wall treatments.
Hallographs to the home listening room is comparable to the finest sound
recording studio designs (I have appraised nearly 20 professional sound
studios in Southern California-it's my job).
This is only the second audio product I am endorsing, the other being
Grover's equipment, ICs and speaker wire. I am doing this as a service
to audiophiles and music lovers (they can be one and the same). There
are other products that I like for which I will have to start a new
forum. I am not in the audio or music business and do not receive
compensation in any way. Try it, you'll like it. Stephen
P.S. I really would like several more pairs, one for my living room
system which has Legacy Sig IIIs and one for the bedroom which has
Dynaco A35s."
http://www.enjoythemusic.com/superio...hallograph.htm
WVK