Woodbury, N.Y. — Infinity has developed a rectangular flat-panel speaker driver said to combine the advantages of circular cone drivers with flat-panel planar-magnetic drivers to create high-accuracy, high-output speakers in small, narrow-baffle enclosures.
Infinity’s proprietary driver technology, called Maximum Radiating Surface (MRS), delivers superior accuracy and higher power-handling capacity at a price lower than slender speakers that incorporate multiple small-cone drivers, said Infinity’s marketing VP Eli Harary.
The technology will appear in a new Cascade speaker series that includes a mix of floorstanding and shelf speakers and a center-channel speaker. The shelf speakers and center-channel speaker can be mounted on shelf stands or on the wall next to a flat-panel TV. Prices on left-right models range from a suggested $699 to $1,499 each, depending on the choice of three finishes. Two powered subwoofer that don’t use the technology retail for a suggested $999 and $1,499 each.
If applied to in-wall speakers, the technology would reduce the size of in-wall cutouts and the size of back-box enclosures.
In the Cascade series, 8-inch by 4-inch MRS drivers deliver midrange and bass frequencies down to about 50Hz. In each Cascade satellite and center-channel speaker, the MRS drivers are complemented by a top-end cone tweeter incorporating Infinity’s proprietary Ceramic Metal Matrix Diaphragm (CMMD) technology, which uses ceramic-coated aluminum-core drivers to extend response out to 40kHz.
MRS drivers with 8-inch by 4-inch dimensions are capable of reproducing bass deeper than 50Hz, but the increased mass and excursion required would, in the first generation, reduce efficiency, said MRS’ inventor An Nguyen. As a result, the Cascade series includes a separately available stand-alone subwoofer that doesn’t use MRS technology.
In outlining MRS’ advantages, Nguyen noted that cone drivers perform well in the bass to midrange bands with good linear excursion, but they require deep mounting depths. Planar-magnetic drivers require little mounting depth but are inefficient, have limited power handling and perform well only at frequencies of 500Hz or more, Nguyen said.
MRS delivers the advantages of both driver technologies, Nguyen explained, by using rectangular high-excursion CMMD drivers whose shape on a narrow baffle provides as much sound-radiating surface area as a round cone driver on a wider baffle. In fact, Nguyen said, MRS offers a “higher ratio of sound-radiating surface area to wasted baffle area” than either cone or planar-magnetic drivers. With cone drivers, the ratio of cone surface area to baffle area is 54 percent, while the ratio of MRS surface area to baffle is 67 percent, Nguyen said.
The greater amount of surface area, combined with MRS’s high-excursion capabilities, means that MRS drivers can push as much air as larger cone drivers, he said. Peak MRS excursion is greater than 25 percent of the driver’s overall depth compared with 10 percent for a cone driver, Nguyen said.
The driver’s shape also yields other benefits. Because it’s narrower than it is taller, the driver delivers a wide, smooth horizontal radiating pattern that delivers a wide sweet spot while minimizing floor and ceiling reflections. The shape and size also help to reduce cone breakup, or flexing, to significantly reduce distortion, the company said.
Infinity builds the rectangular driver out of CMMD material to provide the ultra-low mass and high rigidity that yields quick transient response, high resolution and a resonant frequency outside the audible range, the company said.
Two elliptical voice coils, each almost 8 inches in length, increase the amount of radiating-surface area in contact with the coils, uniformly applying force over the entire surface area and acting as the equivalent of two 5-inch circular voice coils. That design increases efficiency and dynamic range wile also boosting transient response, the company said. The coil’s greater surface area dispels heat more efficiently than circular voice coils, reducing thermal compression and dramatically increasing the speaker’s dynamic range for increased clarity and reduced distortion.
The voice-coil design also improves the time alignment of the low and midrange frequencies that reach a listener’s ears, reducing time-domain distortions that “smear” musical signals, the company said. All frequencies arrive at the listening position at the same time, the company said, because the driver acts more like a pistonic radiator than a cone driver does, with all points on the driver’s surface moving together and in phase. That yields greater detail and resolution, Infinity said.
Cone drivers, in contrast, generate sound first toward the center of the cone, then generate the same sound slightly later at the cone’s perimeter, causing the same signal to arrive at slightly different times at the listener’s ear, Infinity said.
Also to improve sound, Cascade speakers use frameless grilles that attach magnetically to the baffle, eliminating eliminate unwanted reflections that can occur when grille frames are used.
All Cascade models but the $999 subwoofer are due in October to higher end independent A/V dealers, custom installers and select regional chains. The other subwoofer ships in January.
The models are the:
- On-wall/bookshelf Three V with dual MRS drivers and 1-inch tweeter at a suggested $849 each in all three finishes.
- Model Five on-wall/bookshelf with one MRS driver and one tweeter at $$699 each.
- Three C center channel with wall-mount capability, dual MRS drivers flanking a 1-inch tweeter, and suggested retail of $799 each.
- Model Nine floorstanding speaker with two MRS drivers and one tweeter at $999.
- Model Seven floorstanding speaker with one MRS driver and one tweeter at $799.
- Model Fifteen powered sub at $1,499 with four 6-inch by 6-inch non-MRS drivers with 800-watt amp and proprietary RABOS bass-EQ.
- $999 Model 12 10-inch subwoofer with 300 watts and RABOS bass-EQ.