The JBL ES90 is part of the legendary speaker company's mainstream ES Series lineup of home theater and music loudspeakers. At $599 each, suggested retail, the ES90 floor-standing tower is at the top of the ES Series, combining unique wedge-shaped styling with satisfying sound.
The three-way ES90 measures forty-two-and-eleven-sixteenths inches high by ten-and-one-quarter inches wide by fifteen-and-one-eighth inches deep and weighs fifty-three-and-two-fifths pounds - it looks and feels solid. The ES90 employs a three-quarter-inch ultra-high-frequency polyester-film ring-radiator driver, a three-quarter-inch titanium-laminate tweeter, a four-inch PolyPlas-treated midrange and two eight-inch PolyPlas-treated woofers. (PolyPlas is a JBL damping treatment that is used to get a more controlled and smoother response from the drivers.) The ultra-high-frequency transducer's function provides an added sense of spaciousness and treble extension. Even though part of its operating range is inaudible, it's there to help eliminate high-frequency colorations in the audible range and to provide a more natural sense of spaciousness to the speaker's sound. The UHF driver and the tweeter are both mounted in JBL's Elliptical Oblate Spheroidal (EOS) oval-shaped waveguides that are designed to provide good off-axis as well as on-axis coverage and imaging and direct sound towards the listening area rather than off the side walls.
The speaker's frequency response is stated as 36Hz - 40kHz, with an eight-ohm nominal impedance, relatively efficient 91dB sensitivity and a recommended amplifier power rating of 225 watts. The ES90 has two sets of five-way binding posts, enabling the user to bi-wire or bi-amplify the speakers.
Past mainstream JBL models have sometimes been guilty of overly boxy or plain styling. Not so for the ES Series and the ES90 - its enclosure is tapered from front to back, and its front baffle curves into the top surface. The sides of the speakers are finished in a choice of black or cherry, with dark gray front baffles and black grilles. The trapezoidal shape also imparts sonic advantages, avoiding the internal standing waves that can occur in speaker enclosures with parallel sides.