Audio Artistry Team Left to Right: Marshall Kay (President), Don Keele (VP of R&D), Rick Craig (Selah Audio)
Thank you for visiting our room at the 2011 RMAF show. We had a great time showing you our newest product, the CBT36, and we are very excited to hear your impression of this exciting new technology. The CBT36 is available in kit form exclusively from Parts Express and a fully assembled and tested version is available from Audio Artistry, Inc.
We would like to thank the following companies for supporting our demo room with equipment:
CBT36 FLOOR-STANDING CBT CIRCULAR.ARC
HIGH-END LOUDSPEAKER LINE ARRAY
A REVOLUTIONARY NEW SYSTEM BASED ON CBT THEORY:
Marshall Kay and Don Keele of Audio Artistry brought their concept to reality in
conjunction with electronics supplier Parts Express and its Dayton Audio brand of
loudspeaker components to create the CBT36, the world's first broadband constant directivity
(CD) loudspeaker system for the home. The CBT36 system provides
extremely even coverage and flat frequency response at all locations in the listening
CBT, which stands for Constant Beamwidth Transducer, is a loudspeaker line array
technology pioneered by Don Keele in six Audio Engineering Society technical papers,
and is based on unclassified military underwater sound research. See
http://www.dbkeele.com/CBT.php for in-depth information on the CBT concepts.
Each CBT36 contains 18 each 3-1/2" full-range drivers, used as mid woofers, and 72
each 3/4" diameter wide-band tweeters, that are crossed over at 1 kHz. Initially, the
system will only be available in a bi-amped version but later a passive crossover may be
offered. The drivers are mounted on a front panel that has a 36° circular-arc with the
system standing about five feet tall and a width of about 7 inches, and a depth at the
base of about 25 inches.
The 3-1/2" drivers are Dayton Audio's ND91, which were designed specifically for the
CBT36 system. The ND91 utilizes a Neo-Balanced 1" underhung motor that is capable
of over 10 mm of peak excursion and features a shorting ring to help keep distortion
under control. The 3/4" diameter tweeters are also made by Dayton Audio, and are
mounted on pc boards in groups of four to ease assembly and optimize center to center
SPECIFICALLY DESIGNED TO ELIMINATE THE DETRIMENTAL EFFECTS OF FLOOR
The CBT36 has been specifically designed to operate over a reflective ground plane
and does not suffer from destructive floor-bounce effects. The curved line array of 72
tweeters extends all the way down to the floor to take advantage of the ground-plane
acoustic reflection. Effectively the floor provides a reflective surface that acoustically
extends the array below floor level and thus creates an array that is over 10 feet tall and
controls vertical coverage and directivity down to below 160 Hz!
THE VERTICAL AND HORIZONTAL COVERAGE OF THE CBT36 GREATLY REDUCES
CEILING AND WALL REFLECTIONS:
The above-the-floor vertical coverage of the CBT36 is a narrow 28º which is extremely
stable with frequency. This greatly reduces ceiling reflections as compared to a typical
box style system. In addition, the horizontal coverage which is very broad narrows as
you go around the side of the system, which also significantly minimizes side wall
EXTREMELY EVEN COVERAGE WITH NO SWEET-SPOT LISTENING AXIS:
The system has extremely well-behaved and smooth coverage from locations well
above the array to points even down at floor level, and at distances from directly in front
of the speaker to points in the rear of the listening room. The horizontal coverage is
extremely broad and uniform even out to plus-minus 90 degrees.
The CBT36's variation of loudness with, distance is also very unique. At standing height,
the system's volume level hardly changes over a range from directly in front of the
system to points 10 feet away!
MAXIMUM SPL AND DISTORTION:
The system can be played extremely loud and remains very clean and effortless at all
levels. The large number of drivers minimizes distortion, and driven with powerful
amplifiers the system can generate very-high instantaneous peaks.
At this time, the CBT36 system is only available in kit form. Although the MDF cabinet is
pre-assembled, it needs to be finished. The drivers will also need to be mounted and wired to complete
the system. A comprehensive video is available to ease construction.The system must be bi-amped and requires a DSP-based speaker processor along with
two stereo power amplifiers. For extended bass response below 45 Hz, one or two
powerful subwoofers are required.
COME HEAR AND SEE US IN MARRIOTT ATRIUM LEVEL 4, ROOM 403:
(We're actually going to have mirrors on the floor so you can see the ground plane reflection of the array!)
Note: This whole crazy piece was written by me Don Keele, with some Parts-Express help on the "DRIVERS" section, and I take complete responsibility!
The CBT36 is UPS and Fed-Ex shippable and ships in four cartons,
one for each of the cabinets and two for the drivers and components.
To order visit parts-express.com, call 1-800-338-0531 , or E-mail
PART # 301-980 LIST $2,999.99 PR PRICE $1,980.00 PR