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I have one minor sonic criticism of the Sub-15. Until the vol-
ume is advanced to higher levels, it doesn’t resolve the sensa-
tion of air moving in the recording venue. This is a sensation
that exists in the concert hall and I have heard it reproduced by
the Audio Artistry dipole subwoofers. The Sub-15 gets the
pitch, timbre, and timing of the music right, but the environ-
ment in which the music takes place is a shade to the dry side.
C o n s e q u e n t l y, it is more difficult to perceive the acoustic vol-
ume of the recording site. It will be interesting to explore how
room acoustic treatments effect this characteristic.
Battle Summary – Stand-off
I don’t pretend that all the work described above resulted in a
convincing victory over The Room. At this point, though, I was
close to a draw. The spectral balance of the room was delight-
ful, even though I had minimal damping material on the walls
(just a 12 by 9-foot cotton canvas sheet over the area for the
video screen and a little more propped up in the rear corners).
Despite the great overall spectral balance, an excessive amount
of ambient splash remained in the room, limiting the loudness
levels that could be cleanly attained and smearing images and
information in the soundstage. The bass was better, especially
when listening to classical program material. But popular
music, especially Painted From Memory, wouldn’t let me for-
get that the fight for the lowlands was far from over.
I have two major offenses planned: acoustic treatment of
the first reflection points on the sidewalls and ceiling and the
use of advanced technology to address room-induced distor-
tions. The former is to come first from Acoustic Innovations
and, later, from RPG. The latter arrived from Cambridge Sig-
nal Technologies just in time for a sneak peak.
The SigTech T1100 is one of the most important audio
products to reproduced sound since the introduction of elec-
tricity. The T1100 is a dedicated computer whose sole task is
to analyze the sound of your room in three domains (frequen-
cy, phase, and time). It then develops adaptive filters that
modify the signal and applies those filters to pre-correct the
signal to counteract room distortions. This is an extraordinar-
ily advanced and sophisticated use of digital technology that
promises to mitigate room problems that were previously
intractable.
As much as I had hoped for from the T1100, I was unpre-
pared for the fundamental way it reshaped my aural experi-
ences. First, using the T1100, the subwoofers blended seam-
lessly with the Salons and reached 20 Hz flat. The perfor-
mance I extracted from the Salons and Sub-15, which is
described above, was fully attainable only with the SigTech.
Not that I would change a word about the Revels. The SigTech
confirmed the excellence of the Revels.
You will have to wait until Episode Two for a full report on
the T1100, but I will share this now: The changes it wrought
improved not just the tonality of the music, but the dynamics
and space as well. If you want to know more right now, dig
out your old copies of The Absolute Sound (Issues 113 and
109) and read Robert E. Greene’s comments on the SigTech.
Episode Two – A War On Two Fronts
With the arrival of the SigTech T1100, The Room was thrown
back on its heels. There was reason to hope for a convincing
victory. Before the day could be won, though, the war expand-
ed to another front – the center (Revel Voice) and rear chan-
nels (Revel Embrace) – giving The Room more opportunities
to prevail. How would the design prowess of
Revel fare outside the traditional realm of two-
channels and could the SigTech triumph over a
fully activated room?
To Be Continued
Heartfelt appreciation to Robert E. Greene for his technical
contributions to this article. He is a gentleman and a schol -
ar, as generous with his knowledge as he is passionate about
the science of audio.
REVEL
8500 Balboa Boulevard
Northridge, California 91329
Phone: (818) 830-8777
Source: Manufacturer loan
Price: Salon – $14,200 ($15,500 as tested with high gloss
finish and rosewood panels); Sub-15 – $2,500;
LE-1 – $6,000
RPG DIFFUSER SYSTEMS, INC.
651-C Commerce Drive
Upper Malboro, Maryland 20774
Fax: (301) 249-3912
e-mail: info@rpginc.com
Price: Room Optimizer software program – $99
CAMBRIDGE SIGNAL TECHNOLOGIES, INC.
95 Fulkerson Street
Cambridge, Massachusetts 02141
Phone: (617) 491-8890
M a n u f a c t u r e r I n f o r m a t i o n
Manufacturer’s Response
We thank Tom for his tremendous effort and vigilance in work-
ing to create a listening room that allows more meaningful crit-
ical listening. We are pleased that he found Room Optimizer
and our approach to its utilization to be useful. Through its use,
it becomes evident how inadequate simplistic dimensional
ratios are in the quest for optimum room design.
A couple of clarifications of points Tom made in the review
might be useful to the reader:
Dynamic compression does much more than rob the
music of dynamics during high-level peaks. We have found
that many High End speakers change in sound quality at per-
fectly normal loudness levels. The problem is greatly exacer-
bated by the use of first-order filter networks, smallish voice
coils, or less than optimum crossover points. We believe that
our efforts to combat dynamic compression pay off in
improved neutrality and realism. The lack of dynamic com-
pression is an essential factor in achieving the even tonal bal-
ance to whichTom refers.
To m ’s listening room currently has bare, untreated wa l l s .
A normally furnished or acoustically treated room yields ve ry
d i fferent sound at high frequencies. Since Tom is planning to
treat his room, we look fo rward to his further comments
a fter he has installed room treatment in the next episode of
his saga.
KEVIN VOECKS
REVEL