The LB12 full range model made by the French manufacturer Electro Magnet Speaker was our final choice. This model features exceptional technical specifications i.e. very low Qts, low resonance frequency and a very high and unusual acceleration factor for such a diameter of driver. The paper cone is fitted with a very short center bicone and a shaped phase plug made of massive beech. The frequency response is remarkably linear between 55 Hz and 15 kHz in +/-3 dB. The magnet system implements very thick iron pieces on both sides of a big ferrite. A field coil version is available as an option. The injected aluminum alloy basket has a connector for electric earthing to evacuate static electricity. The corrugated cloth spider has decompression holes.
The intentionally limited volume of the bass reflex load leads to a linear response down to 60 Hz then a 18 db/octave level decrease.
The search for an extra octave in the bass would have required a noticeable increase of the volume and the weight of the enclosure as well as a higher intermodulation distorsion. Moreover this compactness will make integration easier in the listening room. The loudspeaker is internally dampened with a minimum amount of 10 mm woolen felt patches. A blue grey acoustic fabric (available in other colors on request) placed at the back of the port softens the aesthetics. The phase plug is available either varnished or in any RAL color according to customers request.
Two WBT Nextgen 0703-Ag pole terminals are mounted on an aluminum plate at the back of the loudspeaker. They feature a progressive tightening system with damping ring. A 4 mm banana socket is connected to the driver basket for earthing. The Absolue Creations “Tim Reference” internal wiring is used without soldering to avoid any pollution of the signal. A tightening system with Mundorf silver gold foil replaces the binding posts of the driver and fits the Nextgen terminals.