Revel Home Theater (SGHT Review) Page 2
Most speakers do not respond in a linear fashion as the input signal increases: At a certain point, they simply refuse to play any louder. This limits the dynamic range, and it can also cause a speaker's timbre to change at different playback levels; the drivers could have different compression characteristics at different frequencies.
This phenomenon is not news to most speaker manufacturers, and Revel designer Kevin Voecks has carefully selected drive units that minimize the problem without shortchanging other important design criteria. In the Ultima Gem, the two bass/midrange drivers (positioned above and below the tweeter in a so-called D'Appolito configuration) are built in-house to Revel's specifications. The cone is made of titanium, which was selected after extensive laser-interferometry testing. It resembles an inverted dome, with no visible dustcap. The 2" voice coil is edge-wound with flat aluminum wire for maximum sensitivity. The magnets are neodymium, and the design is shielded against stray magnetic radiation. The Gem's 1.1" soft-dome tweeter is a modified design from Scan-Speak. A second tweeter (a less sophisticated design with a 0.75" diaphragm) is mounted on the rear baffle for added high-frequency dispersion.
The Gem can be powered from a single amp, or it can be biamped, thanks to dual 5-way binding posts. There is a six-position level control for the main tweeter on the back panel, along with a three-position control (two level settings and off) for the rear tweeter. The speaker is a ported design, and the port is located in the rear.
The Gem is designed to be mounted on Revel's own, pre-filled stands, which are shipped from the factory with the sand already loaded to prevent buyers from leaving it out! These stands are an elegant match for the Gems themselves, with complementary wood trim. However, at $1500/pair ($2200/pair with aluminum trim), they're about as costly as stands get; the price clearly reflects the special tooling required to build them, and their limited market: They're designed specifically for the Gems.
The Ultima Voice is a horizontally configured center-channel speaker incorporating the same design philosophy as the other Revel models. However, the only driver it has in common with the Gem is the tweeter. Its midrange is a newly designed 4" driver with a titanium inverted-dome cone, neodymium magnets, and 1.5" voice-coil. The midrange and tweeter are mounted vertically (tweeter on top) in the center of the front baffle. Such a vertical configuration produces the most uniform response from left to right across the seating area.
Flanking these drivers are two 8" woofers, which depart from Revel's metal-cone philosophy as evinced in the other speakers' bass and midrange drivers. With their silver finish, you might think they're metal, but they're made from a mica- and carbon-filled copolymer. Like the other Revel drivers, however, they're shaped like seamless inverted domes. With their 2" voice-coils and long excursions, they are also designed to minimize dynamic compression.
Like the Gem, the magnetically shielded Voice can be single- or bi-wired, and it has a stepped level control for the tweeter. An additional control is provided to optimize the response of the speaker for free-space (stand), flush (in-wall), or top-of-monitor mounting. The stand for the Voice was too high for my setup; I used a makeshift but solid sand-filled block and MDF support to position it just below my projection screen.