JBL Synthesis 1400 Array BG loudspeaker
The use of exposed, vertically oriented, constant-directivity horns for greater accuracy of reproduction at high listening levels has long been a staple of JBL installations in concert venues around the world. When JBL's chief systems designer, Greg Timberssee applied vertical horns to the design of speakers for the home, he found that they increased the three-dimensionality of the speakers' soundstaging. However, as Japanese audio critics dislike the appearance of vertical horns, the horns were arrayed horizontally in the flagship K2 models. But, as JBL's Synthesis line was designed for the US market, Timbers was free to stand the midrange horn up again: it stands atop the 1400 Array BG, though the tweeter is still loaded by a horizontal horn. When I first saw the Synthesis 1400 Array BG ($11,500/pair), I found its vertical horn somewhat disconcerting. It reminded me of a Dr. Seuss characterwhich made me curious to hear how the speaker sounded.
The Synthesis 1400 Array BG is a three-way, 115-lb speaker that stands 46" tall, 15" wide, and 19" deep. Each of its three drivers was developed in-house and is manufactured by JBL. Frequencies from 8 to 40kHz are handled by a horn-loaded 1" titanium-dome tweeter with an edge-wound voice-coil of aluminum wire and a 2" neodymium motor assembly, mounted in the upper lip of a large, prominent, vertically oriented, constant-directivity midrange horn made of JBL's SonoGlass, a mineral-loaded, high-density resin material. This has a claimed dispersion pattern of 60° horizontal by 30° vertical. The midrange driver is a compression type using a 3" aluminum dome treated with JBL's Aquaplas, which is a damping material. This driver also has an edge-wound voice-coil of aluminum wire and a neodymium motor assembly, and handles frequencies from 8kHz down to 750Hz.
These two compression drivers and their respective horns are mounted above the woofer, which uses a 14" cone of Aquaplas-treated pulp and is mounted in the speaker's trapezoidal bass enclosure. The woofer has a rubber surround, a 4" edge-wound voice-coil, and a ferrite motor assembly; it handles frequencies from 750 down to 32Hz. It is loaded with a flared 4" port on the cabinet's rear. According to Greg Timbers, the 1400 Array was designed to be heavy, solid, and free of vibration. The low-frequency enclosure had to be a trapezoid in order to allow the horn module to sit as low as possible, to reduce the distance between the woofer and the drive-units above it. The horn module is attached securely to the top of the woofer enclosure using three Allen-head bolts, the front two of which are concealed by the JBL nameplate.
The crossover network comprises separate circuit boards for the high- and low-frequency sections, these mounted in different places within the low-frequency enclosure to minimize interference between the filter sections. The acoustic crossover slopes are fourth-order (24dB/octave).
Biamping and/or biwiring is made possible by four sizable, machined, five-way binding posts set below the reflex port, near the bottom of the rear panel. The 1400 Array is shipped with flat metal jumpers placed across each pair of terminals for standard two-stranded speaker cable, which is how I connected them to my amplifier. The 1400 Array is available in two finishes: Black Gloss and Wood Grain. The cabinetry, the hardware, and the drive-units look substantial enough to last a lifetime.
Setup and use
The review samples, enclosed in cardboard shipping cartons, weighed a total of 250 lbs. With the help of my wife, I walked the cartons upstairs to my listening room, where I unpacked them. That's when I discovered that the Synthesis 1400 Array BG requires some assembly.