Shelf Speaker System 2.0 JBL LS40 is closer to uncompromising Hi-End

Charles Sprinkle made designer speakers such as Cinema Sound and Control NOW at JBL. Venerable engineer Daniel Ashcraft comes from the other side of the industry he has been with JBL for over 25 years. Way back in 1986 Ashcraft was involved in creating Everest DD55000, later joined K2 project and in 2006 had a hand in creating today’s flagship Everest DD66000. LS lineup consists of 5 speakers: floor-standing models LS80 and LS60, “center” LS Center, active subwoofer LS120P, we will tell in details about the only speaker in the family LS40 shelf speakers.

CONSTRUCTION

The LS40 models, although featuring a bookshelf design, are oversized, not only because of the need to provide a decent working volume for the relatively large 165mm diameter bass driver, but also because of the 3-way speaker configuration.

However, the breakdown of the LS40 is carried out non-standard way, the speakers do not have a separate midrange driver. The area up to 2.6 kHz is covered by the above mentioned bass driver, which turned out to be a MF/LF one. Then the baton is picked up by the horn compression tweeter and from 7kHz to the ultrasonic 38kHz mark -3dB by the UHF converter. 4th order filters with 24dB/octave roll-off slope are applied in the crossover.

The MF/HF driver features a cellulose cone, die-cast aluminum chassis and a magnet system made of neodymium-iron-boron alloy, equipped with a center stroke to ventilate the voice coil winded on a capton Kapton bobbin, a material known for high temperature stability. The speaker is acoustically loaded on the rear reflex port.

Designed for the LS-series 176Nd compression tweeter equipped with an extremely lightweight but rugged 50mm diameter titanium diaphragm. tweeter equipped with a lightweight aluminum voice coil, neodymium magnet and ferrofluid cooling.

New diamond pattern surround extends the range of the loudspeaker, making it easier to match with other speakers. In the tradition of JBL’s higher-end series, the tweeter is housed in a proprietary Bi-Radial horn, which increases sensitivity and controls beam directivity by reducing reflections from room walls, floors and ceilings.

The 015M tweeter is equipped with a 19mm diameter polyamide ring diaphragm. For its acoustic design is used widely used in other series – shallow waveguide EOS Elliptical Oblate Spheroidal , which has a peculiar profile of a flattened ellipsoid.

The purpose of this acoustic lens is the same as that of the Bi-Radial waveguide – to control the directivity of the radiation, preventing unwanted sound interference from the two tweeters.

The prominent phase cap in the center of the tweeter is used to equalize the response of the speaker system in the upper octaves. Diaphragm, suspension and voice coil bobbin 015M formed in the form of a single structure to reduce signal losses, the necessary power to the radiator gives improved motor with neodymium magnet and cooling of the ferromagnetic fluid.

Experienced JBL engineers understand that for good sound, using good speakers and a good crossover is not enough – the sturdiness and acoustic inertia of the cabinet is just as important. The LS40 is made of MDF and is made without parallel surfaces, which reduces the chance of internal standing waves.

The side panels have a slight curve, the width of the body narrows to the back wall, the front with a complex, thanks to the horn radiators, relief is slightly curved. The top of the cabinet is slightly sloped forward and elegantly rounded at the transition to the front panel.

Additional rigidity of the entire structure and a special visual charm of the speakers give wooden side plates, carefully lacquered and covered with mahogany veneer. The manufacturer also offers another choice of finish: black royal lacquer. The LS40 terminal board contains a double set of gold-plated universal connectors, allowing for Bi-Wiring/Bi-Amping speaker connection methods.

51 980 Dollars.