Music instrument speaker

The 4" voice coil in the BMS AD130 stiffens the speaker cone to form a rigid acoustic piston. Combined with suspension which permits long linear excursion, the AD130 produces crisp, accurate bass. The 4" dural center dome is attached directly to the voice coil to form a large, effective high frequency radiator. The shallow curvilinear cone permits an excellent distribution of highs. The large voice coil is made of flat CCA ribbon so that, with small mass, an unusually large amount of conductor is subjected to the lines of force in the gap of the precision-machined Alnico magnet. A pot structure of pure iron provides a low-reluctance return path for the magneto-motive force. Such extremely efficient use is made of the permanent magnet material that stray magnetic fields are virtually non-existent. Tight electrical coupling and meticulous, close-tolerance workmanship combine to produce the most efficient extended range loudspeaker made anywhere. It is unsurpassed in its handling of transients.