Rare collectors item! Great looking speakers to complete your Vintage Akai set-up. All in very good condition, All drivers are working properly and are optically perfect. Fronts are in very good condition. Little signs of use. Like the AE-63, this is a speaker system that uses Akai's own 3 dr (Three Dimensional Radiation) system. The 3 dr system is designed to reproduce a three dimensional sound field by superimposing sound waves reflected from the back wall with direct sound waves from the front unit. The rear baffle is equipped with a mid-range unit and a passive radiator as well as the front baffle. In order to take advantage of the structure of the 3 dr system, we recommend that it be installed 10 to 50 cm away from the rear wall. For the low range, it uses 13 cm cone type woofer using Akai's original new material mainly polypropylene. For the high range, it uses 2.5 cm soft dome type tweeter. The rear panel features a 13 cm cone passive radiator and a newly developed 3.9 cm planar driven isodynamic mid-range unit with a unique structure consisting of a ring-shaped magnetized magnet and an ultra-thin diaphragm with an etched voice coil. The enclosure is designed with a 3-mm aluminum panel mounted in a black-finished cabinet. Method 3-way / 3-speaker / 3 dr System / Bookshelf Type Units Used For low band : 13 cm cone type For high-pass : 2.5 cm dome type For Rear Middle Area : 3.9 cm Flat Type Other : 13 cm passive radiator Frequency characteristic 70 Hz to 23 kHz Maximum allowable input 60W Rated input (DIN) 30W Impedance 6 Ω Output sound pressure level 89dB/W/m Crossover frequency 7kHz Cutoff frequency Rear mid-range : 2 kHz External dimensions Width 170x Height 280x Depth 146 mm Weight Approx. 3.5 kg Pictures are description also Carefully insured shipped!