Technology & Engineering
Cascade Tapered Array Crossover
Everyone promises that "every seat in the house" gets the best sound. But you have to sit right here in the "sweet spot" to hear it.
Older rear projection televisions had an off-angle viewing issue. If you sat a little to the left or right of the exact center of the projected image on the screen, you couldn’t see it, or you saw ghosting or a dimmer picture. Newer, brighter LCD and plasma televisions have solved this problem. You can usually see your new flat panel television no matter where you sit, even off-angle.
Multi-driver speakers used to have this problem, too. And the explosive growth of multichannel home theater audio, utilizing more speakers in a room than ever before, brought the issue to the forefront. It’s called comb filtering.
Comb filtering happens when multiple speaker drivers, placed close to one another, create destructive interference in the upper midrange. These frequency response errors can degrade imaging, collapse the soundstage and narrow the dispersion of the speakers in the system. Audio sounds thin and unrealistic. Especially if you’re sitting off-angle, where you won't hear important details due to this interference.
Audio Interference Cascades Away!
Polk engineers designed a special cascade tapered array crossover to manipulate the frequency response of individual drivers in multi-driver arrays. In this setup, one driver is crossed over at a much lower frequency, making that driver essentially a bass-only driver in the array. This frees up other drivers to concentrate on more detailed frequencies, such as the upper mid-range. Thus technically separated, performance-robbing interference is tuned right out of the system.
With no comb filtering interference blocking the details, Polk loudspeakers reveal a seamless, lifelike soundstage no matter where you're sitting in your listening room or your home theater. There’s no more sweet spot, because your whole room sounds pretty sweet! You can hear the interference-free imaging impact of the Cascade Tapered Array Crossover in the multi-driver LSi Series, RTi towers, Monitor towers, TSi towers and high-end CSi models.
This article was last modified on Mar 26, 2013